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  • richardmitnick 8:59 am on August 26, 2022 Permalink | Reply
    Tags: "First light observations of chemically rich star HD 222925 captured", , , , Gemini South Telescope upgrade is new next generation high-resolution GHOST spectrograph., Ground based Optical/Infrared Astronomy,   

    From The NSF NOIRLab NOAO Gemini Observatory: “First light observations of chemically rich star HD 222925 captured” 



    Gemini Observatory

    From The NSF NOIRLab NOAO Gemini Observatory

    8.24.22

    Gemini South Telescope upgrade is new next generation high-resolution GHOST spectrograph.

    The U.S. National Science Foundation’s NOIRLab-operated Gemini South Telescope used its latest upgrade — GHOST, the Gemini High-resolution Optical SpecTrograph — to capture observations of HD 222925, a star more than 1,400 light years away. The star, known to be bright and rich in chemicals, is the type of object GHOST is intended to investigate.

    1
    Ultra-high resolution spectrograph, GHOST, captures observable light emissions from distant star.
    Credit: International Gemini Observatory/NOIRLab/NSF/AURA/GHOST Consortium.

    The U.S. National Science Foundation’s NOIRLab-operated Gemini South Telescope used its latest upgrade — GHOST, the Gemini High-resolution Optical SpecTrograph — to capture observations of HD 222925, a star more than 1,400 light years away. The star, known to be bright and rich in chemicals, is the type of object GHOST is intended to investigate.

    “This is an exciting milestone for astronomers around the globe who rely on Gemini South to study the Universe from this exceptional vantage point in Chile,” said Jennifer Lotz, director of the Gemini Observatory. “Once this next-generation instrument is commissioned, GHOST will be an essential component of the astronomer’s toolbox.”

    Spectrographs analyze light emissions from objects and provide information about chemical composition and stellar motion and can observe remnants of the ancient universe. GHOST has ten times the resolution of other visible spectrograph on Gemini South and is the most sensitive high-resolution spectrograph in use among comparably sized telescopes.

    “With the successful commissioning of GHOST, NSF congratulates the instrument team on delivering to the international astronomy community enhanced capability to explore planets, stars, and galaxies,” said Martin Still, Gemini program officer at NSF. “We eagerly await the new discoveries.”

    When the commissioning process is complete, GHOST will be available for all researchers to request observation time.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    _______________________________________________
    Gemini Observatory

    National Science Foundation’s NOIRLab National Optical-Infrared Astronomy Research Laboratory, the US center for ground-based optical-infrared astronomy, operates the international Gemini Observatory (a facility of NSF, NRC–Canada, Gemini Argentina | Argentina.gob.ar, ANID–Chile, Ministry of Science, Technology, Innovation and Communications [Ministério da Ciência, Tecnolgia, Inovação e Comunicações](BR), and Korea Astronomy and Space Science Institute[알림사항])(KR)


    National Science Foundation NOIRLab’s Gemini North Frederick C Gillett telescope at Mauna Kea Observatory Hawai’I, Altitude 4,213 m (13,822 ft).

    Mauna Kea Observatories Hawai’i, altitude 4,213 m (13,822 ft).


    NSF NOIRLab NOAO Gemini South telescope on the summit of Cerro Pachón at an altitude of 7200 feet. There are currently two telescopes commissioned on Cerro Pachón, Gemini South and the Southern Astrophysical Research Telescope. A third, the Vera C. Rubin Observatory, is under construction.


    NSF NOIRLab NOAO Cerro Tololo Inter-American Observatory(CL) approximately 80 km to the East of La Serena, Chile, at an altitude of 2200 meters.
    _______________________________________________


    Gemini’s mission is to advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.

    The NSF NOIRLab Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope, Gemini South, on Cerro Pachón in central Chile); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space.

    The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the National Science Foundation, the Canadian National Research Council, the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica, the Australian Research Council, the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva, and the Brazilian Ministério da Ciência, Tecnologia e Inovação. The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.

    National Science Foundation’s NOIRLab (National Optical-Infrared Astronomy Research Laboratory ), the center for ground-based optical-infrared astronomy, operates the international Gemini Observatory (a facility of NSF, National Research Council Canada (CA), Agancia Nacional de IInvestigacion y Desarrollo (CL), Ministry of Science, Technology and Innovation [Ministério da Ciência, Tecnologia e Inovações] (BR), <a href="http://“>Ministry of Science, Technology and Innovation | Argentina.gob.Ministerio de Ciencia, Tecnología e Innovación | Argentina.gob.(AR), and Korea Astronomy and Space Science Institute[알림사항](KR), Kitt Peak National Observatory (KPNO) , NSF NOAO Cerro Tololo Inter-American Observatory (CL), the NOAO Community Science and Data Center (CSDC), and Vera C. Rubin Observatory in cooperation with DOE’s SLAC National Accelerator Laboratory ).



    It is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with National Science Foundation and is headquartered in Tucson, Arizona.
    The astronomical community is honored to have the opportunity to conduct astronomical research on Iolkam Du’ag (Kitt Peak) in Arizona, on Maunakea in Hawaiʻi, and on Cerro Tololo and Cerro Pachón in Chile. We recognize and acknowledge the very significant cultural role and reverence that these sites have to the Tohono O’odham Nation, to the Native Hawaiian community, and to the local communities in Chile, respectively.

     
  • richardmitnick 4:27 pm on August 18, 2022 Permalink | Reply
    Tags: "Sharpest Image Ever of Universe’s Most Massive Known Star", Ground based Optical/Infrared Astronomy, Groundbreaking observation from Gemini South Observatory suggests this and possibly other colossal stars are less massive than previously thought., The NSF NOIRLab NOAO Gemini South Observatory, The star R136a1- the most massive known star in the Universe.   

    From The NSF NOIRLab NOAO Gemini South Observatory: “Sharpest Image Ever of Universe’s Most Massive Known Star” 



    Gemini Observatory

    From The NSF NOIRLab NOAO Gemini Observatory

    8.18.22

    Venu M. Kalari
    Astronomer
    NSF’s NOIRLab
    Email: venu.kalari@noirlab.edu

    Charles Blue
    Public Information Officer
    NSF’s NOIRLab
    Tel: +1 202 236 6324
    Email: charles.blue@noirlab.edu

    Groundbreaking observation from Gemini South Observatory suggests this and possibly other colossal stars are less massive than previously thought.

    By harnessing the capabilities of the 8.1-meter Gemini South telescope in Chile [below], astronomers have obtained the sharpest image ever of the star R136a1, the most massive known star in the Universe. Their research, led by NOIRLab astronomer Venu M. Kalari, challenges our understanding of the most massive stars and suggests that they may not be as massive as previously thought.

    1
    This is an illustration of R136a1, the largest known star in the Universe, which resides inside the Tarantula Nebula in the Large Magellanic Cloud. Captured with the Zorro instrument on Gemini South. Credit: J. da Silva/Spaceengine/NOIRLab/NSF/AURA.

    Astronomers have yet to fully understand how the most massive stars — those more than 100 times the mass of the Sun — are formed. One particularly challenging piece of this puzzle is obtaining observations of these giants, which typically dwell in the densely populated hearts of dust-shrouded star clusters. Giant stars also live fast and die young, burning through their fuel reserves in only a few million years. In comparison, our Sun is less than halfway through its 10 billion year lifespan. The combination of densely packed stars, relatively short lifetimes, and vast astronomical distances makes distinguishing individual massive stars in clusters a daunting technical challenge.

    By pushing the capabilities of the Zorro instrument on the Gemini South telescope of the International Gemini Observatory, operated by NSF’s NOIRLab, astronomers have obtained the sharpest-ever image of R136a1 — the most massive known star.

    This colossal star is a member of the R136 star cluster, which lies about 160,000 light-years from Earth in the center of the Tarantula Nebula in the Large Magellanic Cloud, a dwarf companion galaxy of the Milky Way.

    Previous observations suggested that R136a1 had a mass somewhere between 250 to 320 times the mass of the Sun. The new Zorro observations, however, indicate that this giant star may be only 170 to 230 times the mass of the Sun. Even with this lower estimate, R136a1 still qualifies as the most massive known star.

    Astronomers are able to estimate a star’s mass by comparing its observed brightness and temperature with theoretical predictions. The sharper Zorro image allowed NSF’s NOIRLab astronomer Venu M. Kalari and his colleagues to more accurately separated the brightness of R136a1 from its nearby stellar companions, which led to a lower estimate of its brightness and therefore its mass.

    “Our results show us that the most massive star we currently know is not as massive as we had previously thought,” explained Kalari, lead author of the paper announcing this result. “This suggests that the upper limit on stellar masses may also be smaller than previously thought.”

    This result also has implications for the origin of elements heavier than helium in the Universe. These elements are created during the cataclysmicly explosive death of stars more than 150 times the mass of the Sun in events that astronomers refer to as pair-instability supernovae. If R136a1 is less massive than previously thought, the same could be true of other massive stars and consequently pair instability supernovae may be rarer than expected.

    The star cluster hosting R136a1 has previously been observed by astronomers using the NASA/ESA Hubble Space Telescope and a variety of ground-based telescopes, but none of these telescopes could obtain images sharp enough to pick out all the individual stellar members of the nearby cluster.

    Gemini South’s Zorro instrument was able to surpass the resolution of previous observations by using a technique known as speckle imaging, which enables ground-based telescopes to overcome much of the blurring effect of Earth’s atmosphere [1]. By taking many thousands of short-exposure images of a bright object and carefully processing the data, it is possible to cancel out almost all this blurring [2]. This approach, as well as the use of adaptive optics, can dramatically increase the resolution of ground-based telescopes, as shown by the team’s sharp new Zorro observations of R136a1 [3].

    “This result shows that given the right conditions an 8.1-meter telescope pushed to its limits can rival not only the Hubble Space Telescope when it comes to angular resolution, but also the James Webb Space Telescope,” commented Ricardo Salinas, a co-author of this paper and the instrument scientist for Zorro. “This observation pushes the boundary of what is considered possible using speckle imaging.”

    “We began this work as an exploratory observation to see how well Zorro could observe this type of object,” concluded Kalari. “While we urge caution when interpreting our results, our observations indicate that the most massive stars may not be as massive as once thought.”

    Zorro and its twin instrument `Alopeke are identical imagers mounted on the Gemini South and Gemini North telescopes, respectively. Their names are the Hawaiian and Spanish words for “fox” and represent the telescopes’ respective locations on Maunakea in Hawai‘i and on Cerro Pachón in Chile. These instruments are part of the Gemini Observatory’s Visiting Instrument Program, which enables new science by accommodating innovative instruments and enabling exciting research. Steve B. Howell, current chair of the Gemini Observatory Board and senior research scientist at the NASA Ames Research Center in Mountain View, California, is the principal investigator on both instruments.

    “Gemini South continues to enhance our understanding of the Universe, transforming astronomy as we know it. This discovery is yet another example of the scientific feats we can accomplish when we combine international collaboration, world-class infrastructure, and a stellar team,” said NSF Gemini Program Officer Martin Still.
    Notes

    [1] The blurring effect of the atmosphere is what makes stars twinkle at night, and astronomers and engineers have devised a variety of approaches to dealing with atmospheric turbulence. As well as placing observatories at high, dry sites with stable skies, astronomers have equipped a handful of telescopes with adaptive optics systems, assemblies of computer-controlled deformable mirrors and laser guide stars that can correct for atmospheric distortion. In addition to speckle imaging, Gemini South is able to use its Gemini Multi-Conjugate Adaptive Optics System to counteract the blurring of the atmosphere.

    [2] The individual observations captured by Zorro had exposure times of just 60 milliseconds, and 40,000 of these individual observations of the R136 cluster were captured over the course of 40 minutes. Each of these snapshots is so short that the atmosphere didn’t have time to blur any individual exposure, and by carefully combining all 40,000 exposures the team could build up a sharp image of the cluster.

    [3] When observing in the red part of the visible electromagnetic spectrum (about 832 nanometers), the Zorro instrument on Gemini South has an image resolution of about 30 milliarcseconds. This is slightly better resolution than NASA/ESA/CSA’s James Webb Space Telescope and about three-times sharper resolution achieved by the Hubble Space Telescope at the same wavelength.

    More information

    This research was presented in the paper “Resolving the core of R136 in the optical” to appear in The Astrophysical Journal [below].

    The team is composed of Venu M. Kalari (Gemini Observatory/NSF’s NOIRLab and Departamento de Astronomia, Universidad de Chile), Elliott P. Horch (Department of Physics, Southern Connecticut State University), Ricardo Salinas (Gemini Observatory/NSF’s NOIRLab), Jorick S. Vink (Armagh Observatory and Planetarium), Morten Andersen (Gemini Observatory/NSF’s NOIRLab and the European Southern Observatory), Joachim M. Bestenlehner (Department of Physics and Astronomy, University of Sheffield), and Monica Rubio (Departamento de Astronomia, Universidad de Chile).

    Science paper:
    The Astrophysical Journal

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    _______________________________________________
    Gemini Observatory

    National Science Foundation’s NOIRLab National Optical-Infrared Astronomy Research Laboratory, the US center for ground-based optical-infrared astronomy, operates the international Gemini Observatory (a facility of NSF, NRC–Canada, Gemini Argentina | Argentina.gob.ar, ANID–Chile, Ministry of Science, Technology, Innovation and Communications [Ministério da Ciência, Tecnolgia, Inovação e Comunicações](BR), and Korea Astronomy and Space Science Institute[알림사항])(KR)


    National Science Foundation NOIRLab’s Gemini North Frederick C Gillett telescope at Mauna Kea Observatory Hawai’I, Altitude 4,213 m (13,822 ft).

    Mauna Kea Observatories Hawai’i, altitude 4,213 m (13,822 ft).


    NSF NOIRLab NOAO Gemini South telescope on the summit of Cerro Pachón at an altitude of 7200 feet. There are currently two telescopes commissioned on Cerro Pachón, Gemini South and the Southern Astrophysical Research Telescope. A third, the Vera C. Rubin Observatory, is under construction.


    NSF NOIRLab NOAO Cerro Tololo Inter-American Observatory(CL) approximately 80 km to the East of La Serena, Chile, at an altitude of 2200 meters.
    _______________________________________________


    Gemini’s mission is to advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.

    The NSF NOIRLab Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope, Gemini South, on Cerro Pachón in central Chile); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space.

    The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the National Science Foundation, the Canadian National Research Council, the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica, the Australian Research Council, the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva, and the Brazilian Ministério da Ciência, Tecnologia e Inovação. The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.

    National Science Foundation’s NOIRLab (National Optical-Infrared Astronomy Research Laboratory ), the center for ground-based optical-infrared astronomy, operates the international Gemini Observatory (a facility of NSF, National Research Council Canada (CA), Agancia Nacional de IInvestigacion y Desarrollo (CL), Ministry of Science, Technology and Innovation [Ministério da Ciência, Tecnologia e Inovações] (BR), <a href="http://“>Ministry of Science, Technology and Innovation | Argentina.gob.Ministerio de Ciencia, Tecnología e Innovación | Argentina.gob.(AR), and Korea Astronomy and Space Science Institute[알림사항](KR), Kitt Peak National Observatory (KPNO) , NSF NOAO Cerro Tololo Inter-American Observatory (CL), the NOAO Community Science and Data Center (CSDC), and Vera C. Rubin Observatory in cooperation with DOE’s SLAC National Accelerator Laboratory ).



    It is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with National Science Foundation and is headquartered in Tucson, Arizona.
    The astronomical community is honored to have the opportunity to conduct astronomical research on Iolkam Du’ag (Kitt Peak) in Arizona, on Maunakea in Hawaiʻi, and on Cerro Tololo and Cerro Pachón in Chile. We recognize and acknowledge the very significant cultural role and reverence that these sites have to the Tohono O’odham Nation, to the Native Hawaiian community, and to the local communities in Chile, respectively.

     
  • richardmitnick 9:58 pm on August 8, 2022 Permalink | Reply
    Tags: , Ground based Optical/Infrared Astronomy, ,   

    From The NSF NOIRLab NOAO Gemini Observatory: “Colliding Galaxies Dazzle in Gemini North Image” 



    Gemini Observatory

    From The NSF NOIRLab NOAO Gemini Observatory

    9 August 2022

    Travis Rector
    NSF’s NOIRLab & University of Alaska
    +1 907 786 1242
    tarector@alaska.edu

    Charles Blue
    Public Information Officer
    NSF’s NOIRLab
    +1 202 236 6324
    charles.blue@noirlab.edu

    NSF’s NOIRLab unveils stunning image of merging spiral galaxies.

    1
    An evocative new image captured by the Gemini North telescope in Hawai‘i reveals a pair of interacting spiral galaxies — NGC 4568 and NGC 4567 — as they begin to clash and merge. These galaxies are entangled by their mutual gravitational field and will eventually combine to form a single elliptical galaxy in around 500 million years. Also visible in the image is the glowing remains of a supernova that was detected in 2020.
    Credit: International Gemini Observatory/NOIRLab/NSF/AURA
    Image processing: T.A. Rector (University of Alaska Anchorage/NSF’s NOIRLab), J. Miller (Gemini Observatory/NSF’s NOIRLab), M. Zamani (NSF’s NOIRLab) & D. de Martin (NSF’s NOIRLab)

    2
    Shown in the image is the glowing remains of a supernova SN 2020fqv (callout box) that was detected in 2020.
    This image from the Gemini North telescope in Hawai‘i reveals a pair of interacting spiral galaxies — NGC 4568 (bottom) and NGC 4567 (top) — as they begin to clash and merge. The galaxies will eventually form a single elliptical galaxy in around 500 million years. Credit: International Gemini Observatory/NOIRLab/NSF/AURA
    Image processing: T.A. Rector (University of Alaska Anchorage/NSF’s NOIRLab), J. Miller (Gemini Observatory/NSF’s NOIRLab), M. Zamani (NSF’s NOIRLab) & D. de Martin (NSF’s NOIRLab)

    Gemini North [below], one of the twin telescopes of the International Gemini Observatory, operated by NSF’s NOIRLab, has observed the initial stages of a cosmic collision approximately 60 million light-years away in the direction of the constellation Virgo. The two stately spiral galaxies, NGC 4568 (bottom) and NGC 4567 (top), are poised to undergo one of the most spectacular events in the Universe, a galactic merger. At present, the centers of these galaxies are still 20,000 light-years apart (about the distance from Earth to the center of the Milky Way) and each galaxy still retains its original, pinwheel shape. Those placid conditions, however, will change.

    As NGC 4568 and NGC 4567 draw together and coalesce, their dueling gravitational forces will trigger bursts of intense stellar formation and wildly distort their once-majestic structures. Over millions of years, the galaxies will repeatedly swing past each other in ever-tightening loops, drawing out long streamers of stars and gas until their individual structures are so thoroughly mixed that a single, essentially spherical, galaxy emerges from the chaos. By that point, much of the gas and dust (the fuel for star formation) in this system will have been used up or blown away.

    This merger is also a preview of what will happen when the Milky Way and its closest large galactic neighbor the Andromeda Galaxy collide in about 5 billion years.

    A bright region in the center of one of NGC 4568’s sweeping spiral arms is the fading afterglow of a supernova — known as SN 2020fqv — that was detected in 2020. The new Gemini image was produced from data taken in 2020.

    By combining decades of observations and computer modeling, astronomers now have compelling evidence that merging spiral galaxies like these go on to become elliptical galaxies. It is likely that NGC 4568 and NGC 4567 will eventually resemble their more-mature neighbor Messier 89, an elliptical galaxy that also resides in the Virgo Cluster. With its dearth of star-forming gas, Messier 89 now exhibits minimal star formation and is made up primarily of older, low-mass stars and ancient globular clusters.

    Advanced technology on the Gemini North telescope, including the Gemini Multi-Object Spectrograph North (GMOS-N) [below] and the dry air above the summit of Maunakea, allowed astronomers to capture this spectacular image.

    The image was obtained by NOIRLab’s Communication, Education & Engagement team, as part of the NOIRLab Legacy Imaging Program.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    _______________________________________________
    Gemini Observatory

    National Science Foundation’s NOIRLab National Optical-Infrared Astronomy Research Laboratory, the US center for ground-based optical-infrared astronomy, operates the international Gemini Observatory (a facility of NSF, NRC–Canada, Gemini Argentina | Argentina.gob.ar, ANID–Chile, Ministry of Science, Technology, Innovation and Communications [Ministério da Ciência, Tecnolgia, Inovação e Comunicações](BR), and Korea Astronomy and Space Science Institute[알림사항])(KR)


    National Science Foundation NOIRLab’s Gemini North Frederick C Gillett telescope at Mauna Kea Observatory Hawai’i Altitude 4,213 m (13,822 ft).

    Mauna Kea Observatories Hawai’i, altitude 4,213 m (13,822 ft).


    NSF NOIRLab NOAO Gemini South telescope (US) on the summit of Cerro Pachón at an altitude of 7200 feet. There are currently two telescopes commissioned on Cerro Pachón, Gemini South and the Southern Astrophysical Research Telescope. A third, the Vera C. Rubin Observatory, is under construction.


    NSF NOIRLab NOAO (US) Cerro Tololo Inter-American Observatory(CL) approximately 80 km to the East of La Serena, Chile, at an altitude of 2200 meters.

    _______________________________________________


    Gemini’s mission is to advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.

    The NSF NOIRLab Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope on Cerro Pachón in central Chile (Gemini South); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space.

    The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the US National Science Foundation (NSF), the Canadian National Research Council (NRC), the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica (CONICYT), the Australian Research Council (ARC), the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva, and the Brazilian Ministério da Ciência, Tecnologia e Inovação. The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.

    National Science Foundation’s NOIRLab (National Optical-Infrared Astronomy Research Laboratory ), the US center for ground-based optical-infrared astronomy, operates the international Gemini Observatory (a facility of NSF, National Research Council Canada (CA), Agancia Nacional de IInvestigacion y Desarrollo (CL), Ministry of Science, Technology and Innovation [Ministério da Ciência, Tecnologia e Inovações] (BR), <a href="http://“>Ministry of Science, Technology and Innovation | Argentina.gob.Ministerio de Ciencia, Tecnología e Innovación | Argentina.gob.(AR), and Korea Astronomy and Space Science Institute[알림사항](KR), Kitt Peak National Observatory (KPNO) , NSF NOAO Cerro Tololo Inter-American Observatory (CL), the NOAO Community Science and Data Center (CSDC), and Vera C. Rubin Observatory in cooperation with DOE’s SLAC National Accelerator Laboratory ).



    It is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with National Science Foundation and is headquartered in Tucson, Arizona.
    The astronomical community is honored to have the opportunity to conduct astronomical research on Iolkam Du’ag (Kitt Peak) in Arizona, on Maunakea in Hawaiʻi, and on Cerro Tololo and Cerro Pachón in Chile. We recognize and acknowledge the very significant cultural role and reverence that these sites have to the Tohono O’odham Nation, to the Native Hawaiian community, and to the local communities in Chile, respectively.

     
  • richardmitnick 8:34 pm on July 26, 2022 Permalink | Reply
    Tags: , , , , , Ground based Optical/Infrared Astronomy, , The neutron star-a pulsar designated PSR J0952-0607,   

    From The W.M. Keck Observatory: “Heaviest Neutron Star to Date is a ‘Black Widow’ Eating its Mate” 

    W.M. Keck Observatory two ten meter telescopes operated by California Institute of Technology and The University of California, at Mauna Kea Observatory, Hawai’i, altitude 4,207 m (13,802 ft). Credit: Caltech.

    Keck Laser Guide Star Adaptive Optics on two 10 meter Keck Observatory telescopes, Mauna Kea Hawai’i, altitude 4,207 m (13,802 ft).

    Mauna Kea Observatories Hawai’i altitude 4,213 m (13,822 ft).

    From The W.M. Keck Observatory

    July 26, 2022

    Mari-Ela Chock (She/Her/Hers)
    Communications Officer
    808.554.0567
    mchock@keck.hawaii.edu

    1
    Artist’s rendition of a ‘spidery’ pulsar. Credit: NASA’s Goddard Space Flight Center.

    A dense, collapsed star spinning 707 times per second — making it one of the fastest spinning neutron stars in the Milky Way galaxy — has shredded and consumed nearly the entire mass of its stellar companion and, in the process, grown into the heaviest neutron star observed to date.

    The study was performed using W. M. Keck Observatory on Maunakea, Hawaiʻi Island and is published in today’s issue of The Astrophysical Journal Letters [below].

    Weighing this record-setting neutron star, which tops the charts at 2.35 times the mass of the Sun, helps astronomers understand the weird quantum state of matter inside these dense objects, which — if they get much heavier than that — collapse entirely and disappear as a black hole.

    “We know roughly how matter behaves at nuclear densities, like in the nucleus of a uranium atom,” said Alex Filippenko, Distinguished Professor of Astronomy at the University of California-Berzerkeley. “A neutron star is like one giant nucleus, but when you have one-and-a-half solar masses of this stuff, which is about 500,000 Earth masses of nuclei all clinging together, it’s not at all clear how they will behave.”

    Stanford University Professor of Astrophysics Roger W. Romani noted that neutron stars are so dense — 1 cubic inch weighs over 10 billion tons — that their cores are the densest matter in the universe short of black holes, which are impossible to study because they are hidden behind their event horizon. The neutron star-a pulsar designated PSR J0952-0607, is thus the densest object within sight of Earth.

    The measurement of the neutron star’s mass was possible thanks to the extreme sensitivity of the 10-meter Keck I telescope. Using Keck Observatory’s Low Resolution Imaging Spectrometer (LRIS) [below], the team was just able to record a spectrum of visible light from the hotly glowing companion star, now reduced to the size of a large gaseous planet. The stars are about 3,000 light years from Earth in the direction of the constellation Sextans.

    2
    Astronomers measured the velocity of a faint star (green circle) that has been stripped of nearly its entire mass by an invisible companion, a neutron star and millisecond pulsar that they determined to be the most massive yet found and perhaps the upper limit for neutron stars. Image credit: Roger W. Romani, Alex Filippenko/W. M. Keck Observatory.

    Discovered in 2017 [The Astrophysical Journal Letters (below)], PSR J0952-0607 is referred to as a “black widow” pulsar — an analogy to the tendency of female black widow spiders to consume the much smaller male after mating. Filippenko and Romani have been studying black widow systems for more than a decade, hoping to establish the upper limit on how large neutron stars/pulsars can grow.

    “By combining this measurement with those of several other black widows, we show that neutron stars must reach at least this mass, 2.35 plus or minus 0.17 solar masses,” said Romani, who is a professor of physics in Stanford’s School of Humanities and Sciences and member of the Kavli Institute for Particle Astrophysics and Cosmology. “In turn, this provides some of the strongest constraints on the property of matter at several times the density seen in atomic nuclei. Indeed, many otherwise popular models of dense-matter physics are excluded by this result.”

    If 2.35 solar masses is close to the upper limit of neutron stars, the researchers say, then the interior is likely to be a soup of neutrons as well as up and down quarks — the constituents of normal protons and neutrons — but not exotic matter, such as “strange” quarks or kaons, which are particles that contain a strange quark.

    “A high maximum mass for neutron stars suggests that it is a mixture of nuclei and their dissolved up and down quarks all the way to the core,” Romani said. “This excludes many proposed states of matter, especially those with exotic interior composition.”

    How large can they grow?

    Astronomers generally agree that when a star with a core larger than about 1.4 solar masses collapses at the end of its life, it forms a dense, compact object with an interior under such high pressure that all atoms are smashed together to form a sea of neutrons and their subnuclear constituents, quarks. These neutron stars are born spinning, and though too dim to be seen in visible light, reveal themselves as pulsars, emitting beams of light — radio waves, X-rays or even gamma rays — that flash Earth as they spin, much like the rotating beam of a lighthouse.

    “Ordinary” pulsars spin and flash about once per second, on average, a speed that can easily be explained given the normal rotation of a star before it collapses. But some pulsars repeat hundreds or up to 1,000 times per second, which is hard to explain unless matter has fallen onto the neutron star and spun it up. But for some millisecond pulsars, no companion is visible.

    One possible explanation for isolated millisecond pulsars is that each did once have a companion, but it stripped it down to nothing.

    “The evolutionary pathway is absolutely fascinating. Double exclamation point,” Filippenko said. “As the companion star evolves and starts becoming a red giant, material spills over to the neutron star, and that spins up the neutron star. By spinning up, it now becomes incredibly energized, and a wind of particles starts coming out from the neutron star. That wind then hits the donor star and starts stripping material off, and over time, the donor star’s mass decreases to that of a planet, and if even more time passes, it disappears altogether. So, that’s how lone millisecond pulsars could be formed. They weren’t all alone to begin with — they had to be in a binary pair — but they gradually evaporated away their companions, and now they’re solitary.”

    The pulsar PSR J0952-0607 and its faint companion star support this origin story for millisecond pulsars.

    “These planet-like objects are the dregs of normal stars which have contributed mass and angular momentum, spinning up their pulsar mates to millisecond periods and increasing their mass in the process,” Romani said.

    “In a case of cosmic ingratitude, the black widow pulsar, which has devoured a large part of its mate, now heats and evaporates the companion down to planetary masses and perhaps complete annihilation,” said Filippenko.

    Spider pulsars include redbacks and tidarrens

    Finding black widow pulsars in which the companion is small, but not too small to detect, is one of few ways to weigh neutron stars. In the case of this binary system, the companion star — now only 20 times the mass of Jupiter — is distorted by the mass of the neutron star and tidally locked, similar to the way our moon is locked in orbit so that we see only one side. The neutron star-facing side is heated to temperatures of about 6,200 Kelvin, or 10,700 degrees Fahrenheit, a bit hotter than our sun, and just bright enough to see with a large telescope.

    Filippenko and Romani turned the Keck I telescope on PSR J0952-0607 on six occasions over the last four years, each time observing with LRIS in 15-minute chunks to catch the faint companion at specific points in its 6.4-hour orbit of the pulsar. By comparing the spectra to that of similar Sun-like stars, they were able to measure the orbital velocity of the companion star and calculate the mass of the neutron star.

    Filippenko and Romani have examined about a dozen black widow systems so far, though only six had companion stars bright enough to let them calculate a mass. All involved neutron stars less massive than the pulsar PSR J0952-060. They’re hoping to study more black widow pulsars, as well as their cousins: redbacks, named for the Australian equivalent of black widow pulsars, which have companions closer to one-tenth the mass of the Sun; and what Romani dubbed tidarrens — where the companion is around one-hundredth of a solar mass — after a relative of the black widow spider. The male of this species, Tidarren sisyphoides, is about 1% of the female’s size.

    “We can keep looking for black widows and similar neutron stars that skate even closer to the black hole brink. But if we don’t find any, it tightens the argument that 2.3 solar masses is the true limit, beyond which they become black holes,” Filippenko said.

    “This is right at the limit of what the Keck telescope can do, so barring fantastic observing conditions, tightening the measurement of PSR J0952-0607 likely awaits the 30-meter telescope era,” added Romani.

    The work was supported by the National Aeronautics and Space Administration (80NSSC17K0024, 80NSSC17K0502), the Christopher R. Redlich Fund, the TABASGO Foundation, and UC Berkeley’s Miller Institute for Basic Research in Science.

    ABOUT LRIS

    The Low Resolution Imaging Spectrometer (LRIS) is a very versatile and ultra-sensitive visible-wavelength imager and spectrograph built at the California Institute of Technology by a team led by Prof. Bev Oke and Prof. Judy Cohen and commissioned in 1993. Since then it has seen two major upgrades to further enhance its capabilities: the addition of a second, blue arm optimized for shorter wavelengths of light and the installation of detectors that are much more sensitive at the longest (red) wavelengths. Each arm is optimized for the wavelengths it covers. This large range of wavelength coverage, combined with the instrument’s high sensitivity, allows the study of everything from comets (which have interesting features in the ultraviolet part of the spectrum), to the blue light from star formation, to the red light of very distant objects. LRIS also records the spectra of up to 50 objects simultaneously, especially useful for studies of clusters of galaxies in the most distant reaches, and earliest times, of the universe. LRIS was used in observing distant supernovae by astronomers who received the Nobel Prize in Physics in 2011 for research determining that the universe was speeding up in its expansion.

    Science papers:
    The Astrophysical Journal Letters 2017

    The Astrophysical Journal Letters 2022

    _______________________________________________
    Women in STEM – Dame Susan Jocelyn Bell Burnell Discovered pulsars


    Biography

    British astrophysicist, scholar and trailblazer Jocelyn Bell Burnell discovered the space-based phenomena known as pulsars, going on to establish herself as an esteemed leader in her field. Who Is Jocelyn Bell Burnell?
    Jocelyn Bell Burnell is a British astrophysicist and astronomer. As a research assistant, she helped build a large radio telescope and discovered pulsars, providing the first direct evidence for the existence of rapidly spinning neutron stars. In addition to her affiliation with Open University, she has served as dean of science at the University of Bath and president of the Royal Astronomical Society. Bell Burnell has also earned countless awards and honors during her distinguished academic career.

    Early Life

    Jocelyn Bell Burnell was born Susan Jocelyn Bell on July 15, 1943, in Belfast, Northern Ireland. Her parents were educated Quakers who encouraged their daughter’s early interest in science with books and trips to a nearby observatory. Despite her appetite for learning, however, Bell Burnell had difficulty in grade school and failed an exam intended to measure her readiness for higher education.

    Undeterred, her parents sent her to England to study at a Quaker boarding school, where she quickly distinguished herself in her science classes. Having proven her aptitude for higher learning, Bell Burnell attended the University of Glasgow, where she earned a bachelor’s degree in physics in 1965.

    Little Green Men

    In 1965, Bell Burnell began her graduate studies in radio astronomy at Cambridge University. One of several research assistants and students working under astronomers Anthony Hewish, her thesis advisor, and Martin Ryle, over the next two years she helped construct a massive radio telescope designed to monitor quasars. By 1967, it was operational and Bell Burnell was tasked with analyzing the data it produced. After spending endless hours pouring over the charts, she noticed some anomalies that did not fit with the patterns produced by quasars and called them to Hewish’s attention.

    Over the ensuing months, the team systematically eliminated all possible sources of the radio pulses—which they affectionately labeled Little Green Men, in reference to their potentially artificial origins—until they were able to deduce that they were made by neutron stars, fast-spinning collapsed stars too small to form black holes.

    Pulsars and Nobel Prize Controversy

    Their findings were published in the February 1968 issue of Nature and caused an immediate sensation. Intrigued as much by the novelty of a woman scientist as by the astronomical significance of the team’s discovery, which was labeled pulsars—for pulsating radio stars—the press picked up the story and showered Bell Burnell with attention. That same year, she earned her Ph.D. in radio astronomy from Cambridge University.

    However, in 1974, only Hewish and Ryle received the Nobel Prize for Physics for their work. Many in the scientific community raised their objections, believing that Bell Burnell had been unfairly snubbed. However, Bell Burnell humbly rejected the notion, feeling that the prize had been properly awarded given her status as a graduate student, though she has also acknowledged that gender discrimination may have been a contributing factor.

    Life on the Electromagnetic Spectrum

    Nobel Prize or not, Bell Burnell’s depth of knowledge regarding radio astronomy and the electromagnetic spectrum has earned her a lifetime of respect in the scientific community and an esteemed career in academia. After receiving her doctorate from Cambridge, she taught and studied gamma ray astronomy at the University of Southampton. Bell Burnell then spent eight years as a professor at University College London, where she focused on x-ray astronomy.

    During this same time, she began her affiliation with Open University, where she would later work as a professor of physics while studying neurons and binary stars, and also conducted research in infrared astronomy at the Royal Observatory, Edinburgh. She was the Dean of Science at the University of Bath from 2001 to 2004, and has been a visiting professor at such esteemed institutions as Princeton University and Oxford University.

    Array of Honors and Achievements

    In recognition of her achievements, Bell Burnell has received countless awards and honors, including Commander and Dame of the Order of the British Empire in 1999 and 2007, respectively; an Oppenheimer prize in 1978; and the 1989 Herschel Medal from the Royal Astronomical Society, for which she would serve as president from 2002 to 2004. She was president of the Institute of Physics from 2008 to 2010, and has served as president of the Royal Society of Edinburgh since 2014. Bell Burnell also has honorary degrees from an array of universities too numerous to mention.

    Personal Life

    In 1968, Jocelyn married Martin Burnell, from whom she took her surname, with the two eventually divorcing in 1993. The two have a son, Gavin, who has also become a physicist.

    A documentary on Bell Burnell’s life, Northern Star, aired on the BBC in 2007.


    Dame Susan Jocelyn Bell Purnell at Perimeter Institute Oct 26, 2018.
    _______________________________________________

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    Mission
    To advance the frontiers of astronomy and share our discoveries with the world.

    The W. M. Keck Observatory operates the largest, most scientifically productive telescopes on Earth. The two, 10-meter optical/infrared telescopes on the summit of Mauna Kea on the Island of Hawaii feature a suite of advanced instruments including imagers, multi-object spectrographs, high-resolution spectrographs, integral-field spectrometer and world-leading laser guide star adaptive optics systems. Keck Observatory is a private 501(c) 3 non-profit organization and a scientific partnership of the California Institute of Technology, the University of California and NASA.

    Today Keck Observatory is supported by both public funding sources and private philanthropy. As a 501(c)3, the organization is managed by The California Association for Research in Astronomy(CARA), whose Board of Directors includes representatives from the California Institute of Technologyand the University of California with liaisons to the board from The National Aeronautics and Space Agencyand the Keck Foundation.


    Keck UCal

    Instrumentation

    Keck 1

    HIRES – The largest and most mechanically complex of the Keck’s main instruments, the High Resolution Echelle Spectrometer breaks up incoming starlight into its component colors to measure the precise intensity of each of thousands of color channels. Its spectral capabilities have resulted in many breakthrough discoveries, such as the detection of planets outside our solar system and direct evidence for a model of the Big Bang theory.

    Keck High-Resolution Echelle Spectrometer (HIRES), at the Keck I telescope.
    LRIS – The Low Resolution Imaging Spectrograph is a faint-light instrument capable of taking spectra and images of the most distant known objects in the universe. The instrument is equipped with a red arm and a blue arm to explore stellar populations of distant galaxies, active galactic nuclei, galactic clusters, and quasars.

    UCO Keck LRIS on Keck 1.

    VISIBLE BAND (0.3-1.0 Micron)

    MOSFIRE – The Multi-Object Spectrograph for Infrared Exploration gathers thousands of spectra from objects spanning a variety of distances, environments and physical conditions. What makes this huge, vacuum-cryogenic instrument unique is its ability to select up to 46 individual objects in the field of view and then record the infrared spectrum of all 46 objects simultaneously. When a new field is selected, a robotic mechanism inside the vacuum chamber reconfigures the distribution of tiny slits in the focal plane in under six minutes. Eight years in the making with First Light in 2012, MOSFIRE’s early performance results range from the discovery of ultra-cool, nearby substellar mass objects, to the detection of oxygen in young galaxies only 2 billion years after the Big Bang.

    Keck/MOSFIRE on Keck 1.

    OSIRIS – The OH-Suppressing Infrared Imaging Spectrograph is a near-infrared spectrograph for use with the Keck I adaptive optics system. OSIRIS takes spectra in a small field of view to provide a series of images at different wavelengths. The instrument allows astronomers to ignore wavelengths where the Earth’s atmosphere shines brightly due to emission from OH (hydroxl) molecules, thus allowing the detection of objects 10 times fainter than previously available.
    Keck OSIRIS on Keck 1.

    Keck 2

    DEIMOS – The Deep Extragalactic Imaging Multi-Object Spectrograph is the most advanced optical spectrograph in the world, capable of gathering spectra from 130 galaxies or more in a single exposure. In ‘Mega Mask’ mode, DEIMOS can take spectra of more than 1,200 objects at once, using a special narrow-band filter.

    Keck/DEIMOS on Keck 2.

    NIRSPEC – The Near Infrared Spectrometer studies very high redshift radio galaxies, the motions and types of stars located near the Galactic Center, the nature of brown dwarfs, the nuclear regions of dusty starburst galaxies, active galactic nuclei, interstellar chemistry, stellar physics, and solar-system science.

    NIRSPEC on Keck 2.

    ESI – The Echellette Spectrograph and Imager captures high-resolution spectra of very faint galaxies and quasars ranging from the blue to the infrared in a single exposure. It is a multimode instrument that allows users to switch among three modes during a night. It has produced some of the best non-AO images at the Observatory.

    KECK Echellette Spectrograph and Imager (ESI).

    KCWI – The Keck Cosmic Web Imager is designed to provide visible band, integral field spectroscopy with moderate to high spectral resolution, various fields of view and image resolution formats and excellent sky-subtraction. The astronomical seeing and large aperture of the telescope enables studies of the connection between galaxies and the gas in their dark matter halos, stellar relics, star clusters and lensed galaxies.

    Keck Cosmic Web Imager on Keck 2 schematic.

    Keck Cosmic Web Imager on Keck 2.

    NEAR-INFRARED (1-5 Micron)

    ADAPTIVE OPTICS – Adaptive optics senses and compensates for the atmospheric distortions of incoming starlight up to 1,000 times per second. This results in an improvement in image quality on fairly bright astronomical targets by a factor 10 to 20.

    LASER GUIDE STAR ADAPTIVE OPTICS [pictured above] – The Keck Laser Guide Star expands the range of available targets for study with both the Keck I and Keck II adaptive optics systems. They use sodium lasers to excite sodium atoms that naturally exist in the atmosphere 90 km (55 miles) above the Earth’s surface. The laser creates an “artificial star” that allows the Keck adaptive optics system to observe 70-80 percent of the targets in the sky, compared to the 1 percent accessible without the laser.

    NIRC-2/AO – The second generation Near Infrared Camera works with the Keck Adaptive Optics system to produce the highest-resolution ground-based images and spectroscopy in the 1-5 micron range. Typical programs include mapping surface features on solar system bodies, searching for planets around other stars, and analyzing the morphology of remote galaxies.

    Keck NIRC2 Camera on Keck 2.
    ABOUT NIRES
    The Near Infrared Echellette Spectrograph (NIRES) is a prism cross-dispersed near-infrared spectrograph built at the California Institute of Technology by a team led by Chief Instrument Scientist Keith Matthews and Prof. Tom Soifer. Commissioned in 2018, NIRES covers a large wavelength range at moderate spectral resolution for use on the Keck II telescope and observes extremely faint red objects found with the Spitzer and WISE infrared space telescopes, as well as brown dwarfs, high-redshift galaxies, and quasars.

    Keck Near-Infrared Echellette Spectrometer on Keck 2.

    Future Instrumentation

    KCRM – The Keck Cosmic Reionization Mapper will complete the Keck Cosmic Web Imager (KCWI), the world’s most capable spectroscopic imager. The design for KCWI includes two separate channels to detect light in the blue and the red portions of the visible wavelength spectrum. KCWI-Blue was commissioned and started routine science observations in September 2017. The red channel of KCWI is KCRM; a powerful addition that will open a window for new discoveries at high redshifts.

    KCRM – Keck Cosmic Reionization Mapper KCRM on Keck 2.

    KPF – The Keck Planet Finder (KPF) will be the most advanced spectrometer of its kind in the world. The instrument is a fiber-fed high-resolution, two-channel cross-dispersed echelle spectrometer for the visible wavelengths and is designed for the Keck II telescope. KPF allows precise measurements of the mass-density relationship in Earth-like exoplanets, which will help astronomers identify planets around other stars that are capable of supporting life.

    KPF Keck Planet Finder on Keck 2.

     
  • richardmitnick 10:36 am on July 26, 2022 Permalink | Reply
    Tags: "Hawaiʻi Telescopes Help Uncover Origins of Castaway Gamma-Ray Bursts", , Ground based Optical/Infrared Astronomy, Mauna Kea Observatories Aid in Revealing That Seemingly Lonely Bursts Came From Previously Undiscovered Galaxies in the Early Universe., The gamma-ray burst identified as GRB 151229A,   

    From The W.M. Keck Observatory: “Hawaiʻi Telescopes Help Uncover Origins of Castaway Gamma-Ray Bursts” 

    W.M. Keck Observatory two ten meter telescopes operated by California Institute of Technology and The University of California, at Mauna Kea Observatory, Hawai’i, altitude 4,207 m (13,802 ft). Credit: Caltech.

    Keck Laser Guide Star Adaptive Optics on two 10 meter Keck Observatory telescopes, Mauna Kea Hawai’i, altitude 4,207 m (13,802 ft).

    Mauna Kea Observatories Hawai’i altitude 4,213 m (13,822 ft).

    From The W.M. Keck Observatory

    July 26, 2022

    Mari-Ela Chock (She/Her/Hers)
    Communications Officer
    808.554.0567
    mchock@keck.hawaii.edu

    Mauna Kea Observatories Aid in Revealing That Seemingly Lonely Bursts Came From Previously Undiscovered Galaxies in the Early Universe.

    1
    Artist’s impression of a merger of two neutron stars, which produces the remarkably brief (1 to 2 second) yet intensely powerful event known as a short gamma-ray burst. Credit: J. da Silva/Spaceengine/NOIRLab/NSF/AURA.

    A number of mysterious gamma-ray bursts appear as lonely flashes of intense energy far from any obvious galactic home, raising questions about their true origins and distances. Using data from some of the most powerful telescopes on Earth and in space, including W. M. Keck Observatory and Gemini North on Mauna Kea, Hawaiʻi, astronomers may have finally found their true origins — a population of distant galaxies, some nearly 10 billion light-years away.


    An international team of astronomers has found that certain short gamma-ray bursts (GRBs) did not originate as castaways in the vastness of intergalactic space as they initially appeared. A deeper multi-observatory study instead found that these seemingly isolated GRBs actually occurred in remarkably distant – and therefore faint – galaxies up to 10 billion light-years away.

    This discovery suggests that short GRBs, which form during the collisions of neutron stars, may have been more common in the past than expected. Since neutron-star mergers forge heavy elements, including gold and platinum, the universe may have been seeded with precious metals earlier than expected as well.

    The study has been accepted for publication in the MNRAS [below].

    “Many short GRBs are found in bright galaxies relatively close to us, but some of them appear to have no corresponding galactic home,” said Brendan O’Connor, lead author of the study and an astronomer at both the University of Maryland and the George Washington University. “By pinpointing where the short GRBs originate, we were able to comb through troves of data from multiple observatories to find the faint glow of galaxies that were simply too distant to be recognized before.”

    Methodology

    This cosmic sleuthing required the combined power of some of the most powerful telescopes on Earth and in space, including two Mauna Kea Observatories in Hawaiʻi – W. M. Keck Observatory and Gemini North telescope [above] – as well as the Gemini South telescope in Chile.


    The two Gemini telescopes comprise the International Gemini Observatory, operated by NSF’s NOIRLab. Other observatories involved in this research include the NASA/ESA Hubble Space Telescope, Lowell Discovery Telescope in Arizona, Gran Telescopio Canarias in Spain, and the European Southern Observatory’s Very Large Telescope in Chile.


    2
    This image captured by the Gemini North telescope on Mauna Kea in Hawaiʻi reveals the previously unrecognized galactic home of the gamma-ray burst identified as GRB 151229A. Astronomers calculate that this burst, which lies in the direction of the constellation Capricornus, occurred approximately 9 billion years ago. Credit: International Gemini Observatory/NOIRLab/NSF/AURA.

    The researchers began their quest by reviewing data on 120 GRBs captured by two instruments aboard NASA’s Neil Gehrels Swift Observatory: Swift’s Burst Alert Telescope, which signaled a burst had been detected; and Swift’s X-ray Telescope, which identified the general location of the GRB’s X-ray afterglow.

    Additional afterglow studies made with the Lowell Observatory more accurately pinpointed the location of the GRBs.

    The afterglow studies found that 43 of the short GRBs were not associated with any known galaxy and appeared in the comparatively empty space between galaxies.

    “These hostless GRBs presented an intriguing mystery and astronomers had proposed two explanations for their seemingly isolated existence,” said O’Connor.

    One hypothesis was that the progenitor neutron stars formed as a binary pair inside a distant galaxy, drifted together into intergalactic space, and eventually merged billions of years later. The other hypothesis was that the neutron stars merged many billions of light-years away in their home galaxies, which now appear extremely faint due to their vast distance from Earth.

    “We felt this second scenario was the most plausible to explain a large fraction of hostless events,” said O’Connor. “We then used the most powerful telescopes on Earth to collect deep images of the GRB locations and uncovered otherwise invisible galaxies 8 to 10 billion light-years away from Earth.”

    To make these detections, the astronomers utilized a variety of optical and infrared instruments, including Keck Observatory’s Low Resolution Imaging Spectrometer (LRIS) [below] and Multi-Object Spectrograph for Infrared Exploration (MOSFIRE) [below], as well as the Gemini Multi-Object Spectrograph mounted on both Gemini North and Gemini South.

    What’s Next

    This result could help astronomers better understand the chemical evolution of the universe. Merging neutron stars trigger a cascading series of nuclear reactions that are necessary to produce heavy metals, like gold, platinum, and thorium. Pushing back the cosmic timescale on neutron-star mergers means that the young universe was far richer in heavy elements than previously known.

    “This pushes the timescale back on when the universe received the ‘Midas touch’ and became seeded with the heaviest elements on the periodic table,” said O’Connor.

    ABOUT LRIS

    The Low Resolution Imaging Spectrometer (LRIS) is a very versatile and ultra-sensitive visible-wavelength imager and spectrograph built at the California Institute of Technology by a team led by Prof. Bev Oke and Prof. Judy Cohen and commissioned in 1993. Since then, it has seen two major upgrades to further enhance its capabilities: the addition of a second, blue arm optimized for shorter wavelengths of light and the installation of detectors that are much more sensitive at the longest (red) wavelengths. Each arm is optimized for the wavelengths it covers. This large range of wavelength coverage, combined with the instrument’s high sensitivity, allows the study of everything from comets (which have interesting features in the ultraviolet part of the spectrum), to the blue light from star formation, to the red light of very distant objects. LRIS also records the spectra of up to 50 objects simultaneously, especially useful for studies of clusters of galaxies in the most distant reaches, and earliest times, of the universe. LRIS was used in observing distant supernovae by astronomers who received the Nobel Prize in Physics in 2011 for research determining that the universe was speeding up in its expansion.

    ABOUT MOSFIRE

    The Multi-Object Spectrograph for Infrared Exploration (MOSFIRE), gathers thousands of spectra from objects spanning a variety of distances, environments and physical conditions. What makes this large, vacuum-cryogenic instrument unique is its ability to select up to 46 individual objects in the field of view and then record the infrared spectrum of all 46 objects simultaneously. When a new field is selected, a robotic mechanism inside the vacuum chamber reconfigures the distribution of tiny slits in the focal plane in under six minutes. Eight years in the making with First Light in 2012, MOSFIRE’s early performance results range from the discovery of ultra-cool, nearby substellar mass objects, to the detection of oxygen in young galaxies only two billion years after the Big Bang. MOSFIRE was made possible by funding provided by the National Science Foundation.

    Science paper:
    MNRAS

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.


    Stem Education Coalition

    Mission
    To advance the frontiers of astronomy and share our discoveries with the world.

    The W. M. Keck Observatory operates the largest, most scientifically productive telescopes on Earth. The two, 10-meter optical/infrared telescopes on the summit of Mauna Kea on the Island of Hawaii feature a suite of advanced instruments including imagers, multi-object spectrographs, high-resolution spectrographs, integral-field spectrometer and world-leading laser guide star adaptive optics systems. Keck Observatory is a private 501(c) 3 non-profit organization and a scientific partnership of the California Institute of Technology, the University of California and NASA.

    Today Keck Observatory is supported by both public funding sources and private philanthropy. As a 501(c)3, the organization is managed by The California Association for Research in Astronomy(CARA), whose Board of Directors includes representatives from the California Institute of Technologyand the University of California with liaisons to the board from The National Aeronautics and Space Agencyand the Keck Foundation.


    Keck UCal

    Instrumentation

    Keck 1

    HIRES – The largest and most mechanically complex of the Keck’s main instruments, the High Resolution Echelle Spectrometer breaks up incoming starlight into its component colors to measure the precise intensity of each of thousands of color channels. Its spectral capabilities have resulted in many breakthrough discoveries, such as the detection of planets outside our solar system and direct evidence for a model of the Big Bang theory.

    Keck High-Resolution Echelle Spectrometer (HIRES), at the Keck I telescope.
    LRIS – The Low Resolution Imaging Spectrograph is a faint-light instrument capable of taking spectra and images of the most distant known objects in the universe. The instrument is equipped with a red arm and a blue arm to explore stellar populations of distant galaxies, active galactic nuclei, galactic clusters, and quasars.

    UCO Keck LRIS on Keck 1.

    VISIBLE BAND (0.3-1.0 Micron)

    MOSFIRE – The Multi-Object Spectrograph for Infrared Exploration gathers thousands of spectra from objects spanning a variety of distances, environments and physical conditions. What makes this huge, vacuum-cryogenic instrument unique is its ability to select up to 46 individual objects in the field of view and then record the infrared spectrum of all 46 objects simultaneously. When a new field is selected, a robotic mechanism inside the vacuum chamber reconfigures the distribution of tiny slits in the focal plane in under six minutes. Eight years in the making with First Light in 2012, MOSFIRE’s early performance results range from the discovery of ultra-cool, nearby substellar mass objects, to the detection of oxygen in young galaxies only 2 billion years after the Big Bang.

    Keck/MOSFIRE on Keck 1.

    OSIRIS – The OH-Suppressing Infrared Imaging Spectrograph is a near-infrared spectrograph for use with the Keck I adaptive optics system. OSIRIS takes spectra in a small field of view to provide a series of images at different wavelengths. The instrument allows astronomers to ignore wavelengths where the Earth’s atmosphere shines brightly due to emission from OH (hydroxl) molecules, thus allowing the detection of objects 10 times fainter than previously available.
    Keck OSIRIS on Keck 1.

    Keck 2

    DEIMOS – The Deep Extragalactic Imaging Multi-Object Spectrograph is the most advanced optical spectrograph in the world, capable of gathering spectra from 130 galaxies or more in a single exposure. In ‘Mega Mask’ mode, DEIMOS can take spectra of more than 1,200 objects at once, using a special narrow-band filter.

    Keck/DEIMOS on Keck 2.

    NIRSPEC – The Near Infrared Spectrometer studies very high redshift radio galaxies, the motions and types of stars located near the Galactic Center, the nature of brown dwarfs, the nuclear regions of dusty starburst galaxies, active galactic nuclei, interstellar chemistry, stellar physics, and solar-system science.

    NIRSPEC on Keck 2.

    ESI – The Echellette Spectrograph and Imager captures high-resolution spectra of very faint galaxies and quasars ranging from the blue to the infrared in a single exposure. It is a multimode instrument that allows users to switch among three modes during a night. It has produced some of the best non-AO images at the Observatory.

    KECK Echellette Spectrograph and Imager (ESI).

    KCWI – The Keck Cosmic Web Imager is designed to provide visible band, integral field spectroscopy with moderate to high spectral resolution, various fields of view and image resolution formats and excellent sky-subtraction. The astronomical seeing and large aperture of the telescope enables studies of the connection between galaxies and the gas in their dark matter halos, stellar relics, star clusters and lensed galaxies.

    Keck Cosmic Web Imager on Keck 2 schematic.

    Keck Cosmic Web Imager on Keck 2.

    NEAR-INFRARED (1-5 Micron)

    ADAPTIVE OPTICS – Adaptive optics senses and compensates for the atmospheric distortions of incoming starlight up to 1,000 times per second. This results in an improvement in image quality on fairly bright astronomical targets by a factor 10 to 20.

    LASER GUIDE STAR ADAPTIVE OPTICS [pictured above] – The Keck Laser Guide Star expands the range of available targets for study with both the Keck I and Keck II adaptive optics systems. They use sodium lasers to excite sodium atoms that naturally exist in the atmosphere 90 km (55 miles) above the Earth’s surface. The laser creates an “artificial star” that allows the Keck adaptive optics system to observe 70-80 percent of the targets in the sky, compared to the 1 percent accessible without the laser.

    NIRC-2/AO – The second generation Near Infrared Camera works with the Keck Adaptive Optics system to produce the highest-resolution ground-based images and spectroscopy in the 1-5 micron range. Typical programs include mapping surface features on solar system bodies, searching for planets around other stars, and analyzing the morphology of remote galaxies.

    Keck NIRC2 Camera on Keck 2.
    ABOUT NIRES
    The Near Infrared Echellette Spectrograph (NIRES) is a prism cross-dispersed near-infrared spectrograph built at the California Institute of Technology by a team led by Chief Instrument Scientist Keith Matthews and Prof. Tom Soifer. Commissioned in 2018, NIRES covers a large wavelength range at moderate spectral resolution for use on the Keck II telescope and observes extremely faint red objects found with the Spitzer and WISE infrared space telescopes, as well as brown dwarfs, high-redshift galaxies, and quasars.

    Keck Near-Infrared Echellette Spectrometer on Keck 2.

    Future Instrumentation

    KCRM – The Keck Cosmic Reionization Mapper will complete the Keck Cosmic Web Imager (KCWI), the world’s most capable spectroscopic imager. The design for KCWI includes two separate channels to detect light in the blue and the red portions of the visible wavelength spectrum. KCWI-Blue was commissioned and started routine science observations in September 2017. The red channel of KCWI is KCRM; a powerful addition that will open a window for new discoveries at high redshifts.

    KCRM – Keck Cosmic Reionization Mapper KCRM on Keck 2.

    KPF – The Keck Planet Finder (KPF) will be the most advanced spectrometer of its kind in the world. The instrument is a fiber-fed high-resolution, two-channel cross-dispersed echelle spectrometer for the visible wavelengths and is designed for the Keck II telescope. KPF allows precise measurements of the mass-density relationship in Earth-like exoplanets, which will help astronomers identify planets around other stars that are capable of supporting life.

    KPF Keck Planet Finder on Keck 2.

     
  • richardmitnick 12:51 pm on April 6, 2022 Permalink | Reply
    Tags: "Astronomers glimpse giant planet in its infancy", , Ground based Optical/Infrared Astronomy, The newly forming planet dubbed AB Aurigae b,   

    From The University of Arizona: “Astronomers glimpse giant planet in its infancy” 

    From The University of Arizona

    4.4.22
    Daniel Stolte
    Science Writer, University Communications
    stolte@arizona.edu
    520-626-4402

    In what is possibly the first direct evidence of a planet forming during an “intense and violent” breakup of a disk of swirling gas and dust, a nascent gas giant was spotted a long distance from its host star.

    1
    Artist’s impression of Aurigae b, a gas giant estimated to be nine times more massive than Jupiter and twice as far from its host planet as Pluto is from the sun. Credit: Joseph Olmsted (The Space Telescope Science Institute)The National Aeronautics and Space Agency, The European Space Agency [La Agencia Espacial Europea] [Agence spatiale européenne][Europäische Weltraumorganisation](EU).)

    A team of astronomers including researchers from the University of Arizona has discovered evidence of a giant planet in the process of forming. This provides the first-ever look at the earliest stages of the formation of a gas giant planet, when it’s still embedded in the disk of gas and dust surrounding its young host star.

    Published in the April 4 issue of Nature Astronomy, the study provides evidence for a long-debated alternative theory for how Jupiter-like planets form: through an “intense and violent” breakup of the protoplanetary disk, according to the authors.

    The dominant theory thought to underlie the formation of giant gas planets is called “core accretion” – a bottom-up process in which planets embedded in a disk of gas and solids grow from smaller objects, ranging from dust- to boulder-sized, colliding and sticking together as they orbit a star. This core then slowly accretes gas. In contrast, “disk instability” is a top-down process in which a massive, gaseous protoplanetary disk cools, and gravity causes the disk to rapidly break up into one or more planet-mass fragments.

    Located 505 light-years from Earth, AB Aurigae is a fairly young star estimated to be around 2 million years old, about the age of our solar system when planet formation was underway. The newly forming planet dubbed AB Aurigae b, is probably about 9 times more massive than Jupiter and orbits its host star at a whopping distance of 8.6 billion miles – about twice the distance between the sun and Pluto. At that distance, Aurigae b is highly unlikely to be the product of core accretion, the authors write, and its origin is better explained by a breakup of AB Aurigae’s protoplanetary disk.

    Led by researchers with the National Astronomical Observatory of Japan’s Subaru Telescope, the University of Tokyo and the Astrobiology Center of Japan, the international research team used the Subaru Telescope’s extreme adaptive optics system, coupled with its infrared spectrograph, or CHARIS, and its visible camera, dubbed VAMPIRES, as well as the Hubble Space Telescope.

    The analysis combines data from two Hubble instruments, the Space Telescope Imaging Spectrograph and the Near Infrared Camera and Multi-Object Spectrometer, with data from the Subaru Telescope’s powerful, dedicated exoplanet imaging instrument, called the Subaru Coronagraphic Extreme Adaptive Optics planet imaging instrument, or SCExAO. The wealth of data from space- and ground-based telescopes proved critical, because distinguishing between infant planets and complex disk features masquerading as planets is very difficult.

    2
    Subaru Coronagraphic Extreme Adaptive Optics planet imaging instrument, or SCExAO.


    Planet-forming disks around stars are not featureless blobs but can have cavities, gaps or regions where different densities produce spiral waves. Such features are very faint, and to detect them, astronomers need sophisticated instruments and techniques such as coronagraphs – telescope attachments designed to block the glare from the host star – and complex image processing algorithms.

    UArizona researchers played key roles in overcoming a major challenge of the study: how to distinguish between a true planet and structural features resulting from the disk being distorted, corrupted or reshaped in some way, and residual artifacts after image processing. Nature itself also provided a helping hand – the vast disk of dust and gas swirling around the star AB Aurigae is tilted nearly face-on to our view from Earth.

    Lead study author Thayne Currie, an astrophysicist with the Subaru Telescope, said Hubble’s longevity played an important role in helping researchers measure the protoplanet’s orbit. He was originally skeptical that AB Aurigae b was a planet. The archival data from Hubble, combined with imaging from Subaru, helped change his mind.

    “We could not detect this motion on the order of a year or two years,” he said. “Hubble provided a time baseline, combined with Subaru data, of 13 years, which was sufficient to be able to detect orbital motion.”

    3
    Subaru Telescope image of the protoplanetary disk around AB Aurigae, a star more than 500 light-years from Earth. UArizona scientists were instrumental in analyzing key features such as spiral arms and the bright signal of the forming gas giant. Credit: T. Currie/Subaru Telescope.

    According to co-author Glenn Schneider, emeritus research professor of astronomy at the UArizona College of Science’s Steward Observatory, combining Hubble’s visible-light instrument, called STIS, and near-infrared instrument, called NICMOS – each outfitted with a coronagraph – provided the necessary one-two punch.

    “New, optimally designed STIS imaging unambiguously allowed us to disentangle light emitted by the disk and the planet from the background ‘pollution’ of residual starlight and create visible-light images of the highest fidelity,” he said. “NICMOS, with much improved reprocessing of near-infrared data obtained 13 years earlier, provided us with the time baseline needed to study planetary motion in the disk.”

    The Subaru Telescope’s SCExAO exoplanet imaging system further helped the team distinguish a protoplanet buried in a disk from a small structural feature in the disk itself.

    “Subaru Telescope’s extreme adaptive optics pulled AB Aur b’s image from the bright structured disk surrounding the star, allowing our infrared and visible instruments to then confirm its nature,” said Olivier Guyon, an astronomer at Steward Observatory and professor at UArizona College of Optical Sciences who serves as the principal investigator of the SCExAO instrument.

    Kevin Wagner, a NASA Hubble/Sagan Fellow at Steward Observatory, played a key role in disentangling the various different possibilities of disk structures masquerading for planets and building robust evidence for the presence of a giant planet.

    “The spiral arm features we observed in this disk are just what we should expect if we have a planet with the mass of Jupiter or more in the presence of these dust structures,” Wagner said. “A massive planet should perturb them into exactly like what we are seeing here.”

    According to Currie, the contributions from the team at UArizona were extremely important to the effort, which “sheds new light on our understanding of the different ways that planets form.”

    “It really took an accumulation of evidence from the ground and from space before we reached the conclusion that this was actually a planet,” Currie said. Understanding the early epochs of the formation of Jupiter-like planets provides astronomers with more context for the history of our own solar system. This discovery paves the way for future studies of the chemical makeup of protoplanetary disks like AB Aurigae, including study with NASA’s James Webb Space Telescope. The 8.2-meter Subaru Telescope is a large optical-infrared telescope operated by the National Astronomical Observatory of Japan, part of Japan’s National Institutes of Natural Sciences, with the support of the MEXT Project to Promote Large Scientific Frontiers. The team is honored and grateful for the opportunity to observe the universe from Maunakea, a mountain with cultural, historical and natural significance in Hawaii.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    As of 2019, the The University of Arizona enrolled 45,918 students in 19 separate colleges/schools, including The University of Arizona College of Medicine in Tucson and Phoenix and the James E. Rogers College of Law, and is affiliated with two academic medical centers (Banner – University Medical Center Tucson and Banner – University Medical Center Phoenix). The University of Arizona is one of three universities governed by the Arizona Board of Regents. The university is part of the Association of American Universities and is the only member from Arizona, and also part of the Universities Research Association . The university is classified among “R1: Doctoral Universities – Very High Research Activity”.

    Known as the Arizona Wildcats (often shortened to “Cats”), The University of Arizona’s intercollegiate athletic teams are members of the Pac-12 Conference of the NCAA. The University of Arizona athletes have won national titles in several sports, most notably men’s basketball, baseball, and softball. The official colors of the university and its athletic teams are cardinal red and navy blue.

    After the passage of the Morrill Land-Grant Act of 1862, the push for a university in Arizona grew. The Arizona Territory’s “Thieving Thirteenth” Legislature approved The University of Arizona in 1885 and selected the city of Tucson to receive the appropriation to build the university. Tucson hoped to receive the appropriation for the territory’s mental hospital, which carried a $100,000 allocation instead of the $25,000 allotted to the territory’s only university Arizona State University was also chartered in 1885, but it was created as Arizona’s normal school, and not a university). Flooding on the Salt River delayed Tucson’s legislators, and by the time they reached Prescott, back-room deals allocating the most desirable territorial institutions had been made. Tucson was largely disappointed with receiving what was viewed as an inferior prize.

    With no parties willing to provide land for the new institution, the citizens of Tucson prepared to return the money to the Territorial Legislature until two gamblers and a saloon keeper decided to donate the land to build the school. Construction of Old Main, the first building on campus, began on October 27, 1887, and classes met for the first time in 1891 with 32 students in Old Main, which is still in use today. Because there were no high schools in Arizona Territory, the university maintained separate preparatory classes for the first 23 years of operation.

    Research

    The University of Arizona is classified among “R1: Doctoral Universities – Very high research activity”. UArizona is the fourth most awarded public university by National Aeronautics and Space Administration for research. The University of Arizona was awarded over $325 million for its Lunar and Planetary Laboratory (LPL) to lead NASA’s 2007–08 mission to Mars to explore the Martian Arctic, and $800 million for its OSIRIS-REx mission, the first in U.S. history to sample an asteroid.

    National Aeronautics Space Agency OSIRIS-REx Spacecraft.

    The LPL’s work in the Cassini spacecraft orbit around Saturn is larger than any other university globally.

    National Aeronautics and Space Administration/European Space Agency [La Agencia Espacial Europea][Agence spatiale européenne][Europäische Weltraumorganisation](EU)/ASI Italian Space Agency [Agenzia Spaziale Italiana](IT) Cassini Spacecraft.

    The University of Arizona laboratory designed and operated the atmospheric radiation investigations and imaging on the probe. The University of Arizona operates the HiRISE camera, a part of the Mars Reconnaissance Orbiter.

    U Arizona NASA Mars Reconnaisance HiRISE Camera.

    NASA Mars Reconnaissance Orbiter.

    While using the HiRISE camera in 2011, University of Arizona alumnus Lujendra Ojha and his team discovered proof of liquid water on the surface of Mars—a discovery confirmed by NASA in 2015. The University of Arizona receives more NASA grants annually than the next nine top NASA/JPL-Caltech-funded universities combined. As of March 2016, The University of Arizona’s Lunar and Planetary Laboratory is actively involved in ten spacecraft missions: Cassini VIMS; Grail; the HiRISE camera orbiting Mars; the Juno mission orbiting Jupiter; Lunar Reconnaissance Orbiter (LRO); Maven, which will explore Mars’ upper atmosphere and interactions with the sun; Solar Probe Plus, a historic mission into the Sun’s atmosphere for the first time; Rosetta’s VIRTIS; WISE; and OSIRIS-REx, the first U.S. sample-return mission to a near-earth asteroid, which launched on September 8, 2016.

    3
    NASA – GRAIL Flying in Formation (Artist’s Concept). Credit: NASA.
    National Aeronautics Space Agency Juno at Jupiter.

    NASA/Lunar Reconnaissance Orbiter.

    NASA/Mars MAVEN

    NASA Parker Solar Probe Plus named to honor Pioneering Physicist Eugene Parker. The Johns Hopkins University Applied Physics Lab.
    National Aeronautics and Space Administration Wise/NEOWISE Telescope.

    The University of Arizona students have been selected as Truman, Rhodes, Goldwater, and Fulbright Scholars. According to The Chronicle of Higher Education, UArizona is among the top 25 producers of Fulbright awards in the U.S.

    The University of Arizona is a member of the Association of Universities for Research in Astronomy , a consortium of institutions pursuing research in astronomy. The association operates observatories and telescopes, notably Kitt Peak National Observatory just outside Tucson.

    National Science Foundation NOIRLab National Optical Astronomy Observatory Kitt Peak National Observatory on Kitt Peak of the Quinlan Mountains in the Arizona-Sonoran Desert on the Tohono O’odham Nation, 88 kilometers (55 mi) west-southwest of Tucson, Arizona, Altitude 2,096 m (6,877 ft). annotated.

    Led by Roger Angel, researchers in the Steward Observatory Mirror Lab at The University of Arizona are working in concert to build the world’s most advanced telescope. Known as the Giant Magellan Telescope (CL), it will produce images 10 times sharper than those from the Earth-orbiting Hubble Telescope.

    GMT Giant Magellan Telescope(CL) 21 meters, to be at the Carnegie Institution for Science’s NOIRLab NOAO Las Campanas Observatory(CL), some 115 km (71 mi) north-northeast of La Serena, Chile, over 2,500 m (8,200 ft) high.

    The telescope is set to be completed in 2021. GMT will ultimately cost $1 billion. Researchers from at least nine institutions are working to secure the funding for the project. The telescope will include seven 18-ton mirrors capable of providing clear images of volcanoes and riverbeds on Mars and mountains on the moon at a rate 40 times faster than the world’s current large telescopes. The mirrors of the Giant Magellan Telescope will be built at The University of Arizona and transported to a permanent mountaintop site in the Chilean Andes where the telescope will be constructed.

    Reaching Mars in March 2006, the Mars Reconnaissance Orbiter contained the HiRISE camera, with Principal Investigator Alfred McEwen as the lead on the project. This National Aeronautics and Space Agency mission to Mars carrying the UArizona-designed camera is capturing the highest-resolution images of the planet ever seen. The journey of the orbiter was 300 million miles. In August 2007, The University of Arizona, under the charge of Scientist Peter Smith, led the Phoenix Mars Mission, the first mission completely controlled by a university. Reaching the planet’s surface in May 2008, the mission’s purpose was to improve knowledge of the Martian Arctic. The Arizona Radio Observatory , a part of The University of Arizona Department of Astronomy Steward Observatory , operates the Submillimeter Telescope on Mount Graham.

    University of Arizona Radio Observatory at NOAO Kitt Peak National Observatory, AZ USA, U Arizona Department of Astronomy and Steward Observatory at altitude 2,096 m (6,877 ft).

    Kitt Peak National Observatory in the Arizona-Sonoran Desert 88 kilometers 55 mi west-southwest of Tucson, Arizona in the Quinlan Mountains of the Tohono O’odham Nation, altitude 2,096 m (6,877 ft)

    The National Science Foundation funded the iPlant Collaborative in 2008 with a $50 million grant. In 2013, iPlant Collaborative received a $50 million renewal grant. Rebranded in late 2015 as “CyVerse”, the collaborative cloud-based data management platform is moving beyond life sciences to provide cloud-computing access across all scientific disciplines.

    In June 2011, the university announced it would assume full ownership of the Biosphere 2 scientific research facility in Oracle, Arizona, north of Tucson, effective July 1. Biosphere 2 was constructed by private developers (funded mainly by Texas businessman and philanthropist Ed Bass) with its first closed system experiment commencing in 1991. The university had been the official management partner of the facility for research purposes since 2007.

    U Arizona mirror lab-Where else in the world can you find an astronomical observatory mirror lab under a football stadium?

    University of Arizona’s Biosphere 2, located in the Sonoran desert. An entire ecosystem under a glass dome? Visit our campus, just once, and you’ll quickly understand why The University of Arizona is a university unlike any other.

    University of Arizona Landscape Evolution Observatory at Biosphere 2.

     
  • richardmitnick 9:42 pm on March 29, 2022 Permalink | Reply
    Tags: "Stellar motions reveal backbone of the Large Magellanic Cloud", Ground based Optical/Infrared Astronomy,   

    From The Leibniz Institute for Astrophysics [Leibniz-Institut für Astrophysik](DE): “Stellar motions reveal backbone of the Large Magellanic Cloud” 

    From The Leibniz Institute for Astrophysics [Leibniz-Institut für Astrophysik](DE)

    March 29, 2022

    Dr. Florian Niederhofer
    Science contact
    fniederhofer@aip.de

    Prof. Dr.
    Maria-Rosa Cioni
    Science contact
    Phone: +49 331 7499 651
    mcioni@aip.de

    Sarah Hönig
    Media contact
    Phone: +49 331 7499 803
    presse@aip.de

    1
    Observed orbits of stars within the central parts of the Large Magellanic Cloud. The stars in the central region, along the bar, follow elongated orbits which deviate from a circular shape (dashed contours).
    Credit: AIP/F. Niederhofer, VISTA VMC Survey.

    Using data from the VISTA survey of the Magellanic Clouds system (VMC), researchers at the Leibniz Institute for Astrophysics Potsdam (AIP), in collaboration with scientists from the VMC team, confirmed the existence of elongated orbits which are at the backbone of the bar formation process. The method used repeated imaging observations to construct a velocity map of stars in the central region of the Large Magellanic Cloud.

    The Large Magellanic Cloud (LMC) is visible by naked eye from the southern hemisphere as it is the brightest and most massive satellite galaxy of the Milky Way.

    The LMC is rich in stars that span a large age range, from newly forming stars to stars as old as the universe. It is classified as an irregular galaxy because it is characterized by a single spiral arm and a bar which is offset from the centre of the disc.

    “Stellar bar structures are a common feature in spiral galaxies. They are believed to form from small perturbations within the stellar disc that remove stars from their circular motions and force them on elongated orbits,” explains Florian Niederhofer, first author of the now published study [MNRAS]. “ The VISTA telescope was developed to survey the southern sky at near-infrared wavelengths to study sources that emit preferentially in this spectral domain, because of either their nature or the presence of dust. Using data from the VMC survey, the team has now found the first direct evidence for these orbits within the bar of the LMC. VMC is a multi-epoch survey of the Magellanic system and a public survey project of the European Southern Observatory (ESO), carried out between 2010 and 2018, aiming to study the stellar content and dynamics of our closest extragalactic neighbours.

    2
    The barred spiral galaxy NGC 1300, considered to be prototypical of barred spiral galaxies. Barred spirals differ from normal spiral galaxies in that the arms of the galaxy do not spiral all the way into the center, but are connected to the two ends of a straight bar of stars containing the nucleus at its center.
    Credit: The National Aeronautics and Space Administration, The European Space Agency [La Agencia Espacial Europea] [Agence spatiale européenne][Europäische Weltraumorganisation](EU), and The Hubble Heritage Team (The Space Telescope Science Institute/The Association of Universities for Research in Astronomy).

    The team developed a sophisticated method to accurately determine proper motions of stars within the Magellanic Clouds. In a new study, now published in MNRAS [above], this method was applied to central parts of the LMC. From the measured values, the authors computed the actual stellar motions within the frame of the LMC, producing detailed velocity maps of the galaxy’s internal velocity structure. “The stunning level of detail in velocity maps shows how much our method has improved, compared with early measurements some years ago,” says Thomas Schmidt, co-author and doctoral student at AIP. To the researchers’ astonishment, their maps revealed elongated stellar motions that follow the structure and orientation of the bar.

    “Thanks to their close proximity of about 163,000 light-years, we can observe individual stars within the Magellanic Clouds using ground-based telescopes like VISTA [above],” says Maria-Rosa Cioni, principal investigator of the VMC project and head of the Dwarf Galaxies and the Galactic Halo section at AIP. “Thus, these galaxies provide us with a unique laboratory to study in great detail the processes that shape and form galaxies.” Of great interest are the dynamics of the stars, since they bear valuable information about the formation and evolution of the galaxies. However, for a long time, the one-dimensional line-of-sight velocities of stars have been the only source of dynamical information. These velocities can readily be measured by spectroscopic Doppler shifts, which rely on the effect that the observed light of a star appears bluer or redder depending on whether it approaches or moves away from us. In order to obtain the full three-dimensional velocities of the stars, it is necessary to know the proper motions of the stars, which are the apparent two-dimensional motions of the stars in the plane of the sky. These motions can be obtained by observing the same stars multiple times over a given time period, typically several years. The displacements of the stars are then determined with respect to nearby reference objects. These objects can be, e.g., very distant background galaxies, which can be assumed to be at rest, given their large distances, or stars with already known proper motions.

    Since the observed motions of stars as seen from Earth are minuscule, precise measurements are still challenging. At the distance of the Magellanic Clouds, the observed motions of the stars are on the order of milli-arcseconds per year – one milli-arcsecond is about the size of an astronaut on the Moon as seen from Earth.

    “Our discovery provides an important contribution to the study of dynamical properties of barred galaxies, since the Magellanic Clouds are at present the only galaxies where such motions can be investigated using stellar proper motions. For more distant galaxies this is still beyond our technical capabilities,” says Florian Niederhofer. In total, it took 9 years of monitoring to accumulate enough images to be able to measure these tiny motions. “This unexpected measurement adds to a number of important results obtained by the VMC team,” proudly adds Maria-Rosa Cioni.

    See the full article here.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Leibniz Institute for Astrophysics Potsdam (DE) is a German research institute. It is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory Potsdam (AOP) founded in 1874. The latter was the world’s first observatory to emphasize explicitly the research area of astrophysics. The AIP was founded in 1992, in a re-structuring following the German reunification.

    The AIP is privately funded and member of the Leibniz Association. It is located in Babelsberg in the state of Brandenburg, just west of Berlin, though the Einstein Tower solar observatory and the great refractor telescope on Telegrafenberg in Potsdam belong to the AIP.

    The key topics of the AIP are cosmic magnetic fields (magnetohydrodynamics) on various scales and extragalactic astrophysics. Astronomical and astrophysical fields studied at the AIP range from solar and stellar physics to stellar and galactic evolution to cosmology.

    The institute also develops research technology in the fields of spectroscopy and robotic telescopes. It is a partner of the Large Binocular Telescope in Arizona, has erected robotic telescopes in Tenerife and the Antarctic, develops astronomical instrumentation for large telescopes such as the VLT of the ESO. Furthermore, work on several e-Science projects are carried out at the AIP.

    LBT-U Arizona Large Binocular Telescope Interferometer, or LBTI, is a ground-based instrument connecting two 8-meter class telescopes on Mount Graham, Arizona, USA, Altitude 3,221 m (10,568 ft.) to form the largest single-mount telescope in the world. The interferometer is designed to detect and study stars and planets outside our solar system. Credit: NASA/JPL-Caltech.

    European Southern Observatory(EU) , Very Large Telescope at Cerro Paranal in the Atacama Desert •ANTU (UT1; The Sun ) •KUEYEN (UT2; The Moon ) •MELIPAL (UT3; The Southern Cross ), and •YEPUN (UT4; Venus – as evening star). Elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo.

    Main research areas

    Magnetohydrodynamics (MHD): Magnetic fields and turbulence in stars, accretion disks and galaxies; computer simulations ao dynamos, magnetic instabilities and magnetic convection
    Solar physics: Observation of sunspots and of solar magnetic field with spectro-polarimetry; Helioseismology and hydrodynamic numerical models; Study of coronal plasma processes by means of radio astronomy; Operation of the Observatory for Solar Radio Astronomy[7] (OSRA) in Tremsdorf, with four radio antennas in different frequency bands from 40 MHz to 800 MHz
    Stellar physics: Numerical simulations of convection in stellar atmospheres, determination of stellar surface parameters and chemical abundances, winds and dust shells of red giants; Doppler tomography of stellar surface structures, development of robotic telescopes, as well as simulation of magnetic flux tubes
    Star formation and the interstellar medium: Brown dwarfs and low-mass stars, circumstellar disks, Origin of double and multiple-star systems
    Galaxies and quasars: Mother galaxies and surroundings of quasars, development of quasars and active galactic cores, structure and the story of the origin of the Milky Way, numerical computer simulations of the origin and development of galaxies
    Cosmology: Numerical simulation of the formation of large-scale structures. Semi-analytic models of galaxy formation and evolution. Predictions for future large observational surveys.

     
  • richardmitnick 10:15 pm on February 25, 2022 Permalink | Reply
    Tags: "NEID-New hunter of potentially habitable planets", Ground based Optical/Infrared Astronomy, , WIYN telescope at the Kitt Peak National Observatory   

    From The National Science Foundation NOIRLab (National Optical-Infrared Astronomy Research Laboratory): “NEID-New hunter of potentially habitable planets” 

    From The National Science Foundation NOIRLab (National Optical-Infrared Astronomy Research Laboratory)

    15 Feb. 2022
    Gemma Lavender

    The NEID instrument, fitted to the 3.5-meter WIYN telescope at the Kitt Peak National Observatory and operated by a consortium of institutions including NOIRLab, is promising to make great strides in the ongoing quest to find other habitable planets around a star other than our Sun.

    To date, astronomers have discovered around 5000 confirmed extrasolar planets, or ‘exoplanets’ for short — worlds orbiting stars other than our Sun. Large, massive planets, or hot planets orbiting close to their star, are easiest to find. Discovering smaller worlds, which orbit in their star’s habitable zone at a greater distance from the star, is tougher.

    Space missions such as NASA’s Kepler Space Telescope and Transiting Exoplanet Survey Satellite (TESS) discover planets by watching for their transits as they cross in front of their host star and block a small percentage of that star’s light.

    The amount of light blocked depends on the size of the transiting planet, and so transits can tell astronomers the diameter of exoplanets, but a transit cannot tell us a planet’s mass. Knowing the mass of an exoplanet is crucial, because once the mass and the diameter are known, it’s a simple calculation to work out an exoplanet’s average density and therefore whether it’s made of gas, liquid/ice, or solid rock.

    That’s why instruments such as NEID, which is NOIRLab’s new planet-hunter installed on the 3.5-meter WIYN telescope, are needed. Pronounced NOO-id, it is named after the Tohono O’odham word for “to see.” NEID ‘sees’ stars ‘wobbling’ by measuring the radial velocity of a star’s light — that is, the Doppler shift of the star’s light as it wobbles towards and away from us.

    3
    The NEID spectrograph, seen under construction at Penn State University.
    Credit: NEID Team/NOIRLab/NSF/The Association of Universities for Research in Astronomy .

    Why would a star wobble? If it’s orbited by an exoplanet, then the exoplanet’s gravity will tug on the star. The star and planet therefore orbit their common center of mass. Because the mass of the star is so great compared to the planet, this center of mass is found within the star, but not at the exact center. So the star appears to wobble around this center of mass. The more massive the planet, the farther from the middle of the star the center of mass is. The wobbling isn’t huge — a star orbited by a Jupiter-sized planet might wobble at a rate of a few dozen km/hr, while an Earth-sized planet in the habitable zone might cause a star to wobble by just 0.4 km/hr.

    So that’s where NEID, which is jointly funded by NASA and the National Science Foundation’s Exoplanet Exploration Program, comes in. “We can say for certain that NEID will break new ground and boost space- and ground-based efforts,” says Jayadev Rajagopal an astronomer at NOIRLab.

    5
    The spectrum of light from the star 51 Pegasi, observed during first light of the NEID instrument. The spectrum can be seen changing from red to blue as the star wobbles towards and away from us, influenced by its orbiting planet.
    Credit: Guðmundur Kári Stefánsson/Princeton University/Penn State University/NOIRLab/NSF/Kitt Peak National Observatory/AURA.

    NEID is designed to nominally detect radial velocities as low as 1 km/hr. During testing NEID even reached a precision slightly better than this as researchers fine-tune the instrument to try and get ever closer to the 0.4 km/hr goal. However, there’s a problem that must first be overcome if that is to be achieved.

    “While the ultimate goal is to be able to detect an Earth-like planet around a Sun-like star, we aren’t there yet,” says Sarah Logsdon, who is an assistant scientist on NEID at NOIRLab in Tucson, Arizona. This is because activity on stars, which causes their brightness to fluctuate and huge clouds of plasma to be ejected in coronal mass ejections, can create a radial velocity signal that swamps that of a small planet. To distinguish the signal of such a world, that stellar activity must first be corrected for.

    7
    The NEID port adaptor, through which optical fibers upon which target stars are trained are fed to the spectrograph. Credit: NOIRLab/NSF/KPNO/AURA.

    “That’s why having the NEID solar telescope is so valuable,” says Logsdon.

    8
    The NEID solar telescope on the roof of the WIYN telescope building.
    Credit: KPNO/NOIRLab/NSF/AURA.

    The solar telescope is just an off-the-shelf, 75mm aperture instrument, funded by the Heising-Simons Foundation and perched atop the roof of the WIYN building at Kitt Peak. Optical fibers feed the view through to the NEID spectrograph, allowing astronomers to calculate a baseline of activity, which can then be applied to other Sun-like stars. Subtracting the stellar baseline from the radial velocity measurements should leave behind just the signal of a planet.

    “NEID’s solar telescope will help us provide a treasure trove of data on stellar variability, helping us to more fully characterize the properties of the host stars that exoplanets orbit,” says Logsdon. “We expect discoveries to come in the very near future.”

    Development on the NEID project began in 2016; it saw first light in 2020 and began science operations in the second half of 2021. Part of its remit is to follow-up on transit discoveries made by the Kepler, K2 and TESS missions, but it will also conduct its own searches for exoplanets, since not all planets in a star system will be seen to transit, and might only be detectable by how their gravity tugs on their host star.

    One exciting project is the NEID Earth Twin Survey, which, over a period of 5 years, will observe some of the nearest and brightest stars, searching for potential radial velocity signals from Earth-sized planets in the habitable zone of their star. Many of these stars will be the same ones being observed by TESS, and in unison TESS and NEID will provide a comprehensive exoplanetary survey of the Sun’s nearest neighbors.

    NEID comes in two parts (three if you include the solar telescope). One is the port adaptor, which is mounted on the WIYN 3.5-meter telescope and enables the targeting and accurate tracking of a star being observed. The precision is so great that the star can be placed on a specific optical fibre that feeds the NEID spectrograph, which is kept in a vacuum chamber at room temperature. This chamber is highly thermally stable — the temperature remains constant to a level of a thousandth of a degree Celsius, which is important to avoid fluctuations that could interfere with the sensitive radial velocity measurements.

    8
    Astronomers crowd around a computer watching the first light data come in from the NEID instrument.
    Credit: S. Ridgway/KPNO/NOIRLab/NSF/AURA.

    “From top to bottom, NEID is designed for precision,” says Rajagopal. “From maximizing the amount of light that reaches the NEID detector, to keeping the spectrograph at a constant temperature, no detail is too small.”

    The WIYN telescope was chosen to host NEID partly because its 3.5-meter mirror is a good match for NEID’s requirements on stellar brightness and signal strength. “But most importantly, NOIRLab and WIYN have a successful and mature infrastructure for federal/university partnerships to allow open access and high-impact science,” says Rajagopal.

    So perhaps, thanks to those partnerships and NEID’s high-precision measurements, astronomers will soon discover a host of potentially habitable, Earth-mass exoplanets that could then be followed up on by facilities such as NASA’s James Webb Space Telescope, to determine if they really have what it takes to be habitable.

    See the full article here.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    What is NOIRLab?

    NSF’s NOIRLab (National Optical-Infrared Astronomy Research Laboratory) (US), the US center for ground-based optical-infrared astronomy, operates the international Gemini Observatory (US) (a facility of National Science Foundation (US), NRC–Canada, ANID–Chile, MCTIC–Brazil, MINCyT–Argentina, and Korea Astronomy and Space Science Institute [한국천문연구원] (KR)), NOAO Kitt Peak National Observatory(US) (KPNO), Cerro Tololo Inter-American Observatory(CL) (CTIO), the Community Science and Data Center (CSDC), and Vera C. Rubin Observatory (in cooperation with DOE’s SLAC National Accelerator Laboratory (US)). It is managed by the Association of Universities for Research in Astronomy (AURA) (US) under a cooperative agreement with NSF and is headquartered in Tucson, Arizona. The astronomical community is honored to have the opportunity to conduct astronomical research on Iolkam Du’ag (Kitt Peak) in Arizona, on Maunakea in Hawaiʻi, and on Cerro Tololo and Cerro Pachón in Chile. We recognize and acknowledge the very significant cultural role and reverence that these sites have to the Tohono O’odham Nation, to the Native Hawaiian community, and to the local communities in Chile, respectively.

    National Science Foundation(US) NOIRLab’s Gemini North Frederick C Gillett telescope at Mauna Kea Observatory Hawai’i (US) Altitude 4,213 m (13,822 ft).

    The National Science Foundation (US) NOIRLab(US) National Optical Astronomy Observatory (US) Gemini South telescope (US) on the summit of Cerro Pachón at an altitude of 7200 feet. There are currently two telescopes commissioned on Cerro Pachón, Gemini South and the SOAR Telescope — Southern Astrophysics Research Telescope. A third, the Vera C. Rubin Observatory, is under construction.

    The National Science Foundation (US) NOIRLab (US) National Optical Astronomy Observatory (US) Vera C. Rubin Observatory [LSST] Telescope currently under construction on the El Peñón peak at Cerro Pachón Chile, a 2,682-meter-high mountain in Coquimbo Region, in northern Chile, alongside the existing NSF (US) NOIRLab (US) NOAO (US) The Association of Universities for Research in Astronomy (AURA)(US) Gemini South Telescope and Southern Astrophysical Research Telescope.

    Carnegie Institution for Science (US)’s Las Campanas Observatory on Cerro Pachón in the southern Atacama Desert of Chile in the Atacama Region approximately 100 kilometres (62 mi) northeast of the city of La Serena,near the southern end and over 2,500 m (8,200 ft) high.

    National Science Foundation(US) NOIRLab (US) National Optical Astronomy Observatory (US) Kitt Peak National Observatory (US) on Kitt Peak of the Quinlan Mountains in the Arizona-Sonoran Desert on the Tohono O’odham Nation, 88 kilometers (55 mi) west-southwest of Tucson, Arizona, Altitude 2,096 m (6,877 ft). annotated.

    NSF NOIRLab NOAO (US) Cerro Tololo Inter-American Observatory(CL) approximately 80 km to the East of La Serena, Chile, at an altitude of 2200 meters.

    The NOAO-Community Science and Data Center(US)

    This work is supported in part by The Department of Energy (US) Office of Science (US). The Dark Energy Survey is a collaboration of more than 400 scientists from 26 institutions in seven countries. Funding for the DES Projects has been provided by the US Department of Energy Office of Science, The National Science Foundation (US), Ministry of Science and Education of Spain, The Science and Technology Facilities Council (UK), The Higher Education Funding Council for England (UK), The Swiss Federal Institute of Technology ETH Zürich [Eidgenössische Technische Hochschule Zürich)](CH), The National Center for Supercomputing Applications (US) at The University of Illinois at Urbana-Champaign (US), The Kavli Institute of Cosmological Physics (US) at The University of Chicago (US), Center for Cosmology and AstroParticle Physics at The Ohio State University (US), Mitchell Institute for Fundamental Physics and Astronomy at The Texas A&M University (US), Brazil Funding Authority for Studies and Projects for Scientific and Technological Development [Financiadora de Estudos e Projetos ] (BR) , Carlos Chagas Filho Foundation for Research Support of the State of Rio de Janeiro [Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro](BR), The Ministry of Science and Technology [Conselho Nacional de Desenvolvimento Científico e Tecnológico and Ministério da Ciência e Tecnologia(BR), German Research Foundation [Deutsche Forschungsgemeinschaft](DE), and the collaborating institutions in the Dark Energy Survey.

    The National Center for Supercomputing Applications(US) at The University of Illinois at Urbana-Champaign (US) provides supercomputing and advanced digital resources for the nation’s science enterprise. At NCSA, The University of Illinois (US) faculty, staff, students, and collaborators from around the globe use advanced digital resources to address research grand challenges for the benefit of science and society. NCSA has been advancing one-third of the Fortune 50® for more than 30 years by bringing industry, researchers, and students together to solve grand challenges at rapid speed and scale.

    DOE’s Fermi National Accelerator Laboratory (US) is America’s premier national laboratory for particle physics and accelerator research. A Department of Energy (US) Office of Science laboratory, Fermilab is located near Chicago, Illinois, and operated under contract by the Fermi Research Alliance LLC, a joint partnership between The University of Chicago (US) and The Universities Research Association, Inc (US).

    The DOE Office of Science (US) is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time.

     
  • richardmitnick 9:54 am on February 20, 2022 Permalink | Reply
    Tags: "Three galaxies are tearing each other apart in stunning new Hubble telescope image", Ground based Optical/Infrared Astronomy, , , , The galaxy cluster IC 2431.   

    From Hubblesite and From ESA/Hubble via Live Science (US): “Three galaxies are tearing each other apart in stunning new Hubble telescope image” 

    National Aeronautics and Space Administration(US)/European Space Agency [La Agencia Espacial Europea] [Agence spatiale européenne] [Europäische Weltraumorganisation](EU) Hubble Space Telescope.

    From Hubblesite and From ESA/Hubble

    via

    Live Science (US)

    2.19.22
    Brandon Specktor

    This twisty-turny collision is a preview of what awaits our galaxy.

    1
    Three galaxies collide in this stunning new Hubble image. (Image credit:
    Hubble Space Telescope – NASA/ESA.)

    Corkscrewing through the cosmos, three distant galaxies collide in a stunning new image captured by NASA’s Hubble Space Telescope.

    This cosmic crash is known as a triple galaxy merger, when three galaxies slowly draw each other nearer and tear each other apart with their competing gravitational forces. Mergers like these are common throughout the universe, and all large galaxies — including our own, the Milky Way — owe their size to violent mergers like this one.

    As chaotic as they seem, mergers like these are more about creation than destruction. As gas from the three neighboring galaxies collides and condenses, a vast sea of material from which new stars will emerge is assembled at the center of the newly unified galaxy.

    Existing stars, meanwhile, will survive the crash mostly unscathed; while the gravitational tug-of-war among the three galaxies will warp the orbital paths of many existing stars, so much space exists between those stars that relatively few of them are likely to collide, Live Science previously reported.

    The galaxy cluster seen above is called IC 2431, located about 681 million light-years from Earth in the constellation Cancer, according to NASA. Astronomers detected the merger thanks to a citizen science project called Galaxy Zoo, which invited more than 100,000 volunteers to classify images of 900,000 galaxies captured by the Hubble telescope that were never thoroughly examined. The crowdsourced project accomplished in 175 days what would have taken astronomers years to achieve, according to NASA, and the initiative has already resulted in a number of strange and exciting discoveries, like this one.

    Studying galactic mergers can help astronomers better understand the Milky Way’s past and future. The Milky Way is thought to have gobbled up more than a dozen galaxies over the past 12 billion years, including during the exceptionally named Gaia sausage merger, Live Science previously reported.

    Meanwhile, our galaxy appears on track to combine with the nearby Andromeda galaxy about 4.5 billion years from now. The merger will totally alter the night sky over Earth but will likely leave the solar system unharmed, according to NASA.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition
    The NASA/ESA Hubble Space Telescope is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most versatile, renowned both as a vital research tool and as a public relations boon for astronomy. The Hubble telescope is named after astronomer Edwin Hubble and is one of NASA’s Great Observatories, along with the NASA Compton Gamma Ray Observatory, the Chandra X-ray Observatory, and the NASA Spitzer Infrared Space Telescope.

    National Aeronautics Space Agency (USA) Compton Gamma Ray Observatory
    National Aeronautics and Space Administration(US) Chandra X-ray telescope(US).
    National Aeronautics and Space Administration(US) Spitzer Infrared Apace Telescope no longer in service. Launched in 2003 and retired on 30 January 2020.

    Edwin Hubble at Caltech Palomar Samuel Oschin 48 inch Telescope(US) Credit: Emilio Segre Visual Archives/AIP/SPL.

    Edwin Hubble looking through the 100-inch Hooker telescope at Mount Wilson in Southern California(US), 1929 discovers the Universe is Expanding. Credit: Margaret Bourke-White/Time & Life Pictures/Getty Images.

    Hubble features a 2.4-meter (7.9 ft) mirror, and its four main instruments observe in the ultraviolet, visible, and near-infrared regions of the electromagnetic spectrum. Hubble’s orbit outside the distortion of Earth’s atmosphere allows it to capture extremely high-resolution images with substantially lower background light than ground-based telescopes. It has recorded some of the most detailed visible light images, allowing a deep view into space. Many Hubble observations have led to breakthroughs in astrophysics, such as determining the rate of expansion of the universe.

    The Hubble telescope was built by the United States space agency National Aeronautics Space Agency (US) with contributions from the The European Space Agency [La Agencia Espacial Europea] [Agence spatiale européenne][Europäische Weltraumorganisation](EU). The Space Telescope Science Institute (STScI) selects Hubble’s targets and processes the resulting data, while the NASA Goddard Space Flight Center(US) controls the spacecraft. Space telescopes were proposed as early as 1923. Hubble was funded in the 1970s with a proposed launch in 1983, but the project was beset by technical delays, budget problems, and the 1986 Challenger disaster. It was finally launched by Space Shuttle Discovery in 1990, but its main mirror had been ground incorrectly, resulting in spherical aberration that compromised the telescope’s capabilities. The optics were corrected to their intended quality by a servicing mission in 1993.

    Hubble is the only telescope designed to be maintained in space by astronauts. Five Space Shuttle missions have repaired, upgraded, and replaced systems on the telescope, including all five of the main instruments. The fifth mission was initially canceled on safety grounds following the Columbia disaster (2003), but NASA administrator Michael D. Griffin approved the fifth servicing mission which was completed in 2009. The telescope was still operating as of April 24, 2020, its 30th anniversary, and could last until 2030–2040. One successor to the Hubble telescope is the National Aeronautics Space Agency(USA)/European Space Agency [La Agencia Espacial Europea] [Agence spatiale européenne](EU)/Canadian Space Agency(CA) Webb Infrared Space Telescope launched December 25, 2021, ten years late.
    National Aeronautics Space Agency(USA)/European Space Agency [La Agencia Espacial Europea] [Agence spatiale européenne][Europäische Weltraumorganisation](EU)/ Canadian Space Agency [Agence Spatiale Canadienne](CA) Webb Infrared Space Telescope(US) James Webb Space Telescope annotated . Launched December 25, 2021, ten years late.

    Proposals and precursors

    In 1923, Hermann Oberth—considered a father of modern rocketry, along with Robert H. Goddard and Konstantin Tsiolkovsky—published Die Rakete zu den Planetenräumen (“The Rocket into Planetary Space“), which mentioned how a telescope could be propelled into Earth orbit by a rocket.

    The history of the Hubble Space Telescope can be traced back as far as 1946, to astronomer Lyman Spitzer’s paper entitled Astronomical advantages of an extraterrestrial observatory. In it, he discussed the two main advantages that a space-based observatory would have over ground-based telescopes. First, the angular resolution (the smallest separation at which objects can be clearly distinguished) would be limited only by diffraction, rather than by the turbulence in the atmosphere, which causes stars to twinkle, known to astronomers as seeing. At that time ground-based telescopes were limited to resolutions of 0.5–1.0 arcseconds, compared to a theoretical diffraction-limited resolution of about 0.05 arcsec for an optical telescope with a mirror 2.5 m (8.2 ft) in diameter. Second, a space-based telescope could observe infrared and ultraviolet light, which are strongly absorbed by the atmosphere.

    Spitzer devoted much of his career to pushing for the development of a space telescope. In 1962, a report by the U.S. National Academy of Sciences recommended development of a space telescope as part of the space program, and in 1965 Spitzer was appointed as head of a committee given the task of defining scientific objectives for a large space telescope.

    Space-based astronomy had begun on a very small-scale following World War II, as scientists made use of developments that had taken place in rocket technology. The first ultraviolet spectrum of the Sun was obtained in 1946, and the National Aeronautics and Space Administration (US) launched the Orbiting Solar Observatory (OSO) to obtain UV, X-ray, and gamma-ray spectra in 1962.
    National Aeronautics Space Agency(USA) Orbiting Solar Observatory

    An orbiting solar telescope was launched in 1962 by the United Kingdom as part of the Ariel space program, and in 1966 NASA launched the first Orbiting Astronomical Observatory (OAO) mission. OAO-1’s battery failed after three days, terminating the mission. It was followed by OAO-2, which carried out ultraviolet observations of stars and galaxies from its launch in 1968 until 1972, well beyond its original planned lifetime of one year.

    The OSO and OAO missions demonstrated the important role space-based observations could play in astronomy. In 1968, NASA developed firm plans for a space-based reflecting telescope with a mirror 3 m (9.8 ft) in diameter, known provisionally as the Large Orbiting Telescope or Large Space Telescope (LST), with a launch slated for 1979. These plans emphasized the need for crewed maintenance missions to the telescope to ensure such a costly program had a lengthy working life, and the concurrent development of plans for the reusable Space Shuttle indicated that the technology to allow this was soon to become available.

    Quest for funding

    The continuing success of the OAO program encouraged increasingly strong consensus within the astronomical community that the LST should be a major goal. In 1970, NASA established two committees, one to plan the engineering side of the space telescope project, and the other to determine the scientific goals of the mission. Once these had been established, the next hurdle for NASA was to obtain funding for the instrument, which would be far more costly than any Earth-based telescope. The U.S. Congress questioned many aspects of the proposed budget for the telescope and forced cuts in the budget for the planning stages, which at the time consisted of very detailed studies of potential instruments and hardware for the telescope. In 1974, public spending cuts led to Congress deleting all funding for the telescope project.
    In response a nationwide lobbying effort was coordinated among astronomers. Many astronomers met congressmen and senators in person, and large-scale letter-writing campaigns were organized. The National Academy of Sciences published a report emphasizing the need for a space telescope, and eventually the Senate agreed to half the budget that had originally been approved by Congress.

    The funding issues led to something of a reduction in the scale of the project, with the proposed mirror diameter reduced from 3 m to 2.4 m, both to cut costs and to allow a more compact and effective configuration for the telescope hardware. A proposed precursor 1.5 m (4.9 ft) space telescope to test the systems to be used on the main satellite was dropped, and budgetary concerns also prompted collaboration with the European Space Agency. ESA agreed to provide funding and supply one of the first-generation instruments for the telescope, as well as the solar cells that would power it, and staff to work on the telescope in the United States, in return for European astronomers being guaranteed at least 15% of the observing time on the telescope. Congress eventually approved funding of US$36 million for 1978, and the design of the LST began in earnest, aiming for a launch date of 1983. In 1983 the telescope was named after Edwin Hubble, who confirmed one of the greatest scientific discoveries of the 20th century, made by Georges Lemaitre, that the universe is expanding.

    Construction and engineering

    Once the Space Telescope project had been given the go-ahead, work on the program was divided among many institutions. NASA Marshall Space Flight Center (MSFC) was given responsibility for the design, development, and construction of the telescope, while Goddard Space Flight Center was given overall control of the scientific instruments and ground-control center for the mission. MSFC commissioned the optics company Perkin-Elmer to design and build the Optical Telescope Assembly (OTA) and Fine Guidance Sensors for the space telescope. Lockheed was commissioned to construct and integrate the spacecraft in which the telescope would be housed.

    Optical Telescope Assembly

    Optically, the HST is a Cassegrain reflector of Ritchey–Chrétien design, as are most large professional telescopes. This design, with two hyperbolic mirrors, is known for good imaging performance over a wide field of view, with the disadvantage that the mirrors have shapes that are hard to fabricate and test. The mirror and optical systems of the telescope determine the final performance, and they were designed to exacting specifications. Optical telescopes typically have mirrors polished to an accuracy of about a tenth of the wavelength of visible light, but the Space Telescope was to be used for observations from the visible through the ultraviolet (shorter wavelengths) and was specified to be diffraction limited to take full advantage of the space environment. Therefore, its mirror needed to be polished to an accuracy of 10 nanometers, or about 1/65 of the wavelength of red light. On the long wavelength end, the OTA was not designed with optimum IR performance in mind—for example, the mirrors are kept at stable (and warm, about 15 °C) temperatures by heaters. This limits Hubble’s performance as an infrared telescope.

    Perkin-Elmer intended to use custom-built and extremely sophisticated computer-controlled polishing machines to grind the mirror to the required shape. However, in case their cutting-edge technology ran into difficulties, NASA demanded that PE sub-contract to Kodak to construct a back-up mirror using traditional mirror-polishing techniques. (The team of Kodak and Itek also bid on the original mirror polishing work. Their bid called for the two companies to double-check each other’s work, which would have almost certainly caught the polishing error that later caused such problems.) The Kodak mirror is now on permanent display at the National Air and Space Museum. An Itek mirror built as part of the effort is now used in the 2.4 m telescope at the Magdalena Ridge Observatory.

    Construction of the Perkin-Elmer mirror began in 1979, starting with a blank manufactured by Corning from their ultra-low expansion glass. To keep the mirror’s weight to a minimum it consisted of top and bottom plates, each one inch (25 mm) thick, sandwiching a honeycomb lattice. Perkin-Elmer simulated microgravity by supporting the mirror from the back with 130 rods that exerted varying amounts of force. This ensured the mirror’s final shape would be correct and to specification when finally deployed. Mirror polishing continued until May 1981. NASA reports at the time questioned Perkin-Elmer’s managerial structure, and the polishing began to slip behind schedule and over budget. To save money, NASA halted work on the back-up mirror and put the launch date of the telescope back to October 1984. The mirror was completed by the end of 1981; it was washed using 2,400 US gallons (9,100 L) of hot, deionized water and then received a reflective coating of 65 nm-thick aluminum and a protective coating of 25 nm-thick magnesium fluoride.

    Doubts continued to be expressed about Perkin-Elmer’s competence on a project of this importance, as their budget and timescale for producing the rest of the OTA continued to inflate. In response to a schedule described as “unsettled and changing daily”, NASA postponed the launch date of the telescope until April 1985. Perkin-Elmer’s schedules continued to slip at a rate of about one month per quarter, and at times delays reached one day for each day of work. NASA was forced to postpone the launch date until March and then September 1986. By this time, the total project budget had risen to US$1.175 billion.

    Spacecraft systems

    The spacecraft in which the telescope and instruments were to be housed was another major engineering challenge. It would have to withstand frequent passages from direct sunlight into the darkness of Earth’s shadow, which would cause major changes in temperature, while being stable enough to allow extremely accurate pointing of the telescope. A shroud of multi-layer insulation keeps the temperature within the telescope stable and surrounds a light aluminum shell in which the telescope and instruments sit. Within the shell, a graphite-epoxy frame keeps the working parts of the telescope firmly aligned. Because graphite composites are hygroscopic, there was a risk that water vapor absorbed by the truss while in Lockheed’s clean room would later be expressed in the vacuum of space; resulting in the telescope’s instruments being covered by ice. To reduce that risk, a nitrogen gas purge was performed before launching the telescope into space.

    While construction of the spacecraft in which the telescope and instruments would be housed proceeded somewhat more smoothly than the construction of the OTA, Lockheed still experienced some budget and schedule slippage, and by the summer of 1985, construction of the spacecraft was 30% over budget and three months behind schedule. An MSFC report said Lockheed tended to rely on NASA directions rather than take their own initiative in the construction.

    Computer systems and data processing

    The two initial, primary computers on the HST were the 1.25 MHz DF-224 system, built by Rockwell Autonetics, which contained three redundant CPUs, and two redundant NSSC-1 (NASA Standard Spacecraft Computer, Model 1) systems, developed by Westinghouse and GSFC using diode–transistor logic (DTL). A co-processor for the DF-224 was added during Servicing Mission 1 in 1993, which consisted of two redundant strings of an Intel-based 80386 processor with an 80387-math co-processor. The DF-224 and its 386 co-processor were replaced by a 25 MHz Intel-based 80486 processor system during Servicing Mission 3A in 1999. The new computer is 20 times faster, with six times more memory, than the DF-224 it replaced. It increases throughput by moving some computing tasks from the ground to the spacecraft and saves money by allowing the use of modern programming languages.

    Additionally, some of the science instruments and components had their own embedded microprocessor-based control systems. The MATs (Multiple Access Transponder) components, MAT-1 and MAT-2, utilize Hughes Aircraft CDP1802CD microprocessors. The Wide Field and Planetary Camera (WFPC) also utilized an RCA 1802 microprocessor (or possibly the older 1801 version). The WFPC-1 was replaced by the WFPC-2 [below] during Servicing Mission 1 in 1993, which was then replaced by the Wide Field Camera 3 (WFC3) [below] during Servicing Mission 4 in 2009.

    Initial instruments

    When launched, the HST carried five scientific instruments: the Wide Field and Planetary Camera (WF/PC), Goddard High Resolution Spectrograph (GHRS), High Speed Photometer (HSP), Faint Object Camera (FOC) and the Faint Object Spectrograph (FOS). WF/PC was a high-resolution imaging device primarily intended for optical observations. It was built by NASA JPL-Caltech (US), and incorporated a set of 48 filters isolating spectral lines of particular astrophysical interest. The instrument contained eight charge-coupled device (CCD) chips divided between two cameras, each using four CCDs. Each CCD has a resolution of 0.64 megapixels. The wide field camera (WFC) covered a large angular field at the expense of resolution, while the planetary camera (PC) took images at a longer effective focal length than the WF chips, giving it a greater magnification.

    The GHRS was a spectrograph designed to operate in the ultraviolet. It was built by the Goddard Space Flight Center and could achieve a spectral resolution of 90,000. Also optimized for ultraviolet observations were the FOC and FOS, which were capable of the highest spatial resolution of any instruments on Hubble. Rather than CCDs these three instruments used photon-counting digicons as their detectors. The FOC was constructed by ESA, while the University of California, San Diego(US), and Martin Marietta Corporation built the FOS.

    The final instrument was the HSP, designed and built at the University of Wisconsin–Madison (US). It was optimized for visible and ultraviolet light observations of variable stars and other astronomical objects varying in brightness. It could take up to 100,000 measurements per second with a photometric accuracy of about 2% or better.

    HST’s guidance system can also be used as a scientific instrument. Its three Fine Guidance Sensors (FGS) are primarily used to keep the telescope accurately pointed during an observation, but can also be used to carry out extremely accurate astrometry; measurements accurate to within 0.0003 arcseconds have been achieved.

    Ground support

    The Space Telescope Science Institute (STScI) is responsible for the scientific operation of the telescope and the delivery of data products to astronomers. STScI is operated by the Association of Universities for Research in Astronomy (US) (AURA) and is physically located in Baltimore, Maryland on the Homewood campus of Johns Hopkins University (US), one of the 39 U.S. universities and seven international affiliates that make up the AURA consortium. STScI was established in 1981 after something of a power struggle between NASA and the scientific community at large. NASA had wanted to keep this function in-house, but scientists wanted it to be based in an academic establishment. The Space Telescope European Coordinating Facility (ST-ECF), established at Garching bei München near Munich in 1984, provided similar support for European astronomers until 2011, when these activities were moved to the European Space Astronomy Centre.

    One rather complex task that falls to STScI is scheduling observations for the telescope. Hubble is in a low-Earth orbit to enable servicing missions, but this means most astronomical targets are occulted by the Earth for slightly less than half of each orbit. Observations cannot take place when the telescope passes through the South Atlantic Anomaly due to elevated radiation levels, and there are also sizable exclusion zones around the Sun (precluding observations of Mercury), Moon and Earth. The solar avoidance angle is about 50°, to keep sunlight from illuminating any part of the OTA. Earth and Moon avoidance keeps bright light out of the FGSs, and keeps scattered light from entering the instruments. If the FGSs are turned off, the Moon and Earth can be observed. Earth observations were used very early in the program to generate flat-fields for the WFPC1 instrument. There is a so-called continuous viewing zone (CVZ), at roughly 90° to the plane of Hubble’s orbit, in which targets are not occulted for long periods.

    Challenger disaster, delays, and eventual launch

    By January 1986, the planned launch date of October looked feasible, but the Challenger explosion brought the U.S. space program to a halt, grounding the Shuttle fleet and forcing the launch of Hubble to be postponed for several years. The telescope had to be kept in a clean room, powered up and purged with nitrogen, until a launch could be rescheduled. This costly situation (about US$6 million per month) pushed the overall costs of the project even higher. This delay did allow time for engineers to perform extensive tests, swap out a possibly failure-prone battery, and make other improvements. Furthermore, the ground software needed to control Hubble was not ready in 1986, and was barely ready by the 1990 launch.

    Eventually, following the resumption of shuttle flights in 1988, the launch of the telescope was scheduled for 1990. On April 24, 1990, Space Shuttle Discovery successfully launched it during the STS-31 mission.

    From its original total cost estimate of about US$400 million, the telescope cost about US$4.7 billion by the time of its launch. Hubble’s cumulative costs were estimated to be about US$10 billion in 2010, twenty years after launch.

    List of Hubble instruments

    Hubble accommodates five science instruments at a given time, plus the Fine Guidance Sensors, which are mainly used for aiming the telescope but are occasionally used for scientific astrometry measurements. Early instruments were replaced with more advanced ones during the Shuttle servicing missions. COSTAR was a corrective optics device rather than a science instrument, but occupied one of the five instrument bays.
    Since the final servicing mission in 2009, the four active instruments have been ACS, COS, STIS and WFC3. NICMOS is kept in hibernation, but may be revived if WFC3 were to fail in the future.

    Advanced Camera for Surveys (ACS; 2002–present)
    Cosmic Origins Spectrograph (COS; 2009–present)
    Corrective Optics Space Telescope Axial Replacement (COSTAR; 1993–2009)
    Faint Object Camera (FOC; 1990–2002)
    Faint Object Spectrograph (FOS; 1990–1997)
    Fine Guidance Sensor (FGS; 1990–present)
    Goddard High Resolution Spectrograph (GHRS/HRS; 1990–1997)
    High Speed Photometer (HSP; 1990–1993)
    Near Infrared Camera and Multi-Object Spectrometer (NICMOS; 1997–present, hibernating since 2008)
    Space Telescope Imaging Spectrograph (STIS; 1997–present (non-operative 2004–2009))
    Wide Field and Planetary Camera (WFPC; 1990–1993)
    Wide Field and Planetary Camera 2 (WFPC2; 1993–2009)
    Wide Field Camera 3 (WFC3; 2009–present)

    Of the former instruments, three (COSTAR, FOS and WFPC2) are displayed in the Smithsonian National Air and Space Museum. The FOC is in the Dornier Museum, Germany. The HSP is in the Space Place at the University of Wisconsin–Madison. The first WFPC was dismantled, and some components were then re-used in WFC3.

    Flawed mirror

    Within weeks of the launch of the telescope, the returned images indicated a serious problem with the optical system. Although the first images appeared to be sharper than those of ground-based telescopes, Hubble failed to achieve a final sharp focus and the best image quality obtained was drastically lower than expected. Images of point sources spread out over a radius of more than one arcsecond, instead of having a point spread function (PSF) concentrated within a circle 0.1 arcseconds (485 nrad) in diameter, as had been specified in the design criteria.

    Analysis of the flawed images revealed that the primary mirror had been polished to the wrong shape. Although it was believed to be one of the most precisely figured optical mirrors ever made, smooth to about 10 nanometers, the outer perimeter was too flat by about 2200 nanometers (about 1⁄450 mm or 1⁄11000 inch). This difference was catastrophic, introducing severe spherical aberration, a flaw in which light reflecting off the edge of a mirror focuses on a different point from the light reflecting off its center.

    The effect of the mirror flaw on scientific observations depended on the particular observation—the core of the aberrated PSF was sharp enough to permit high-resolution observations of bright objects, and spectroscopy of point sources was affected only through a sensitivity loss. However, the loss of light to the large, out-of-focus halo severely reduced the usefulness of the telescope for faint objects or high-contrast imaging. This meant nearly all the cosmological programs were essentially impossible, since they required observation of exceptionally faint objects. This led politicians to question NASA’s competence, scientists to rue the cost which could have gone to more productive endeavors, and comedians to make jokes about NASA and the telescope − in the 1991 comedy The Naked Gun 2½: The Smell of Fear, in a scene where historical disasters are displayed, Hubble is pictured with RMS Titanic and LZ 129 Hindenburg. Nonetheless, during the first three years of the Hubble mission, before the optical corrections, the telescope still carried out a large number of productive observations of less demanding targets. The error was well characterized and stable, enabling astronomers to partially compensate for the defective mirror by using sophisticated image processing techniques such as deconvolution.

    Origin of the problem

    A commission headed by Lew Allen, director of the Jet Propulsion Laboratory, was established to determine how the error could have arisen. The Allen Commission found that a reflective null corrector, a testing device used to achieve a properly shaped non-spherical mirror, had been incorrectly assembled—one lens was out of position by 1.3 mm (0.051 in). During the initial grinding and polishing of the mirror, Perkin-Elmer analyzed its surface with two conventional refractive null correctors. However, for the final manufacturing step (figuring), they switched to the custom-built reflective null corrector, designed explicitly to meet very strict tolerances. The incorrect assembly of this device resulted in the mirror being ground very precisely but to the wrong shape. A few final tests, using the conventional null correctors, correctly reported spherical aberration. But these results were dismissed, thus missing the opportunity to catch the error, because the reflective null corrector was considered more accurate.

    The commission blamed the failings primarily on Perkin-Elmer. Relations between NASA and the optics company had been severely strained during the telescope construction, due to frequent schedule slippage and cost overruns. NASA found that Perkin-Elmer did not review or supervise the mirror construction adequately, did not assign its best optical scientists to the project (as it had for the prototype), and in particular did not involve the optical designers in the construction and verification of the mirror. While the commission heavily criticized Perkin-Elmer for these managerial failings, NASA was also criticized for not picking up on the quality control shortcomings, such as relying totally on test results from a single instrument.

    Design of a solution

    Many feared that Hubble would be abandoned. The design of the telescope had always incorporated servicing missions, and astronomers immediately began to seek potential solutions to the problem that could be applied at the first servicing mission, scheduled for 1993. While Kodak had ground a back-up mirror for Hubble, it would have been impossible to replace the mirror in orbit, and too expensive and time-consuming to bring the telescope back to Earth for a refit. Instead, the fact that the mirror had been ground so precisely to the wrong shape led to the design of new optical components with exactly the same error but in the opposite sense, to be added to the telescope at the servicing mission, effectively acting as “spectacles” to correct the spherical aberration.

    The first step was a precise characterization of the error in the main mirror. Working backwards from images of point sources, astronomers determined that the conic constant of the mirror as built was −1.01390±0.0002, instead of the intended −1.00230. The same number was also derived by analyzing the null corrector used by Perkin-Elmer to figure the mirror, as well as by analyzing interferograms obtained during ground testing of the mirror.

    Because of the way the HST’s instruments were designed, two different sets of correctors were required. The design of the Wide Field and Planetary Camera 2, already planned to replace the existing WF/PC, included relay mirrors to direct light onto the four separate charge-coupled device (CCD) chips making up its two cameras. An inverse error built into their surfaces could completely cancel the aberration of the primary. However, the other instruments lacked any intermediate surfaces that could be figured in this way, and so required an external correction device.

    The Corrective Optics Space Telescope Axial Replacement (COSTAR) system was designed to correct the spherical aberration for light focused at the FOC, FOS, and GHRS. It consists of two mirrors in the light path with one ground to correct the aberration. To fit the COSTAR system onto the telescope, one of the other instruments had to be removed, and astronomers selected the High Speed Photometer to be sacrificed. By 2002, all the original instruments requiring COSTAR had been replaced by instruments with their own corrective optics. COSTAR was removed and returned to Earth in 2009 where it is exhibited at the National Air and Space Museum. The area previously used by COSTAR is now occupied by the Cosmic Origins Spectrograph.

    NASA COSTAR

    NASA COSTAR installation

    Servicing missions and new instruments

    Servicing Mission 1

    The first Hubble serving mission was scheduled for 1993 before the mirror problem was discovered. It assumed greater importance, as the astronauts would need to do extensive work to install corrective optics; failure would have resulted in either abandoning Hubble or accepting its permanent disability. Other components failed before the mission, causing the repair cost to rise to $500 million (not including the cost of the shuttle flight). A successful repair would help demonstrate the viability of building Space Station Alpha, however.

    STS-49 in 1992 demonstrated the difficulty of space work. While its rescue of Intelsat 603 received praise, the astronauts had taken possibly reckless risks in doing so. Neither the rescue nor the unrelated assembly of prototype space station components occurred as the astronauts had trained, causing NASA to reassess planning and training, including for the Hubble repair. The agency assigned to the mission Story Musgrave—who had worked on satellite repair procedures since 1976—and six other experienced astronauts, including two from STS-49. The first mission director since Project Apollo would coordinate a crew with 16 previous shuttle flights. The astronauts were trained to use about a hundred specialized tools.

    Heat had been the problem on prior spacewalks, which occurred in sunlight. Hubble needed to be repaired out of sunlight. Musgrave discovered during vacuum training, seven months before the mission, that spacesuit gloves did not sufficiently protect against the cold of space. After STS-57 confirmed the issue in orbit, NASA quickly changed equipment, procedures, and flight plan. Seven total mission simulations occurred before launch, the most thorough preparation in shuttle history. No complete Hubble mockup existed, so the astronauts studied many separate models (including one at the Smithsonian) and mentally combined their varying and contradictory details. Service Mission 1 flew aboard Endeavour in December 1993, and involved installation of several instruments and other equipment over ten days.

    Most importantly, the High-Speed Photometer was replaced with the COSTAR corrective optics package, and WFPC was replaced with the Wide Field and Planetary Camera 2 (WFPC2) with an internal optical correction system. The solar arrays and their drive electronics were also replaced, as well as four gyroscopes in the telescope pointing system, two electrical control units and other electrical components, and two magnetometers. The onboard computers were upgraded with added coprocessors, and Hubble’s orbit was boosted.

    On January 13, 1994, NASA declared the mission a complete success and showed the first sharper images. The mission was one of the most complex performed up until that date, involving five long extra-vehicular activity periods. Its success was a boon for NASA, as well as for the astronomers who now had a more capable space telescope.

    Servicing Mission 2

    Servicing Mission 2, flown by Discovery in February 1997, replaced the GHRS and the FOS with the Space Telescope Imaging Spectrograph (STIS) and the Near Infrared Camera and Multi-Object Spectrometer (NICMOS), replaced an Engineering and Science Tape Recorder with a new Solid State Recorder, and repaired thermal insulation. NICMOS contained a heat sink of solid nitrogen to reduce the thermal noise from the instrument, but shortly after it was installed, an unexpected thermal expansion resulted in part of the heat sink coming into contact with an optical baffle. This led to an increased warming rate for the instrument and reduced its original expected lifetime of 4.5 years to about two years.

    Servicing Mission 3A

    Servicing Mission 3A, flown by Discovery, took place in December 1999, and was a split-off from Servicing Mission 3 after three of the six onboard gyroscopes had failed. The fourth failed a few weeks before the mission, rendering the telescope incapable of performing scientific observations. The mission replaced all six gyroscopes, replaced a Fine Guidance Sensor and the computer, installed a Voltage/temperature Improvement Kit (VIK) to prevent battery overcharging, and replaced thermal insulation blankets.

    Servicing Mission 3B

    Servicing Mission 3B flown by Columbia in March 2002 saw the installation of a new instrument, with the FOC (which, except for the Fine Guidance Sensors when used for astrometry, was the last of the original instruments) being replaced by the Advanced Camera for Surveys (ACS). This meant COSTAR was no longer required, since all new instruments had built-in correction for the main mirror aberration. The mission also revived NICMOS by installing a closed-cycle cooler and replaced the solar arrays for the second time, providing 30 percent more power.

    Servicing Mission 4

    Plans called for Hubble to be serviced in February 2005, but the Columbia disaster in 2003, in which the orbiter disintegrated on re-entry into the atmosphere, had wide-ranging effects on the Hubble program. NASA Administrator Sean O’Keefe decided all future shuttle missions had to be able to reach the safe haven of the International Space Station should in-flight problems develop. As no shuttles were capable of reaching both HST and the space station during the same mission, future crewed service missions were canceled. This decision was criticized by numerous astronomers who felt Hubble was valuable enough to merit the human risk. HST’s planned successor, the James Webb Telescope (JWST), as of 2004 was not expected to launch until at least 2011. A gap in space-observing capabilities between a decommissioning of Hubble and the commissioning of a successor was of major concern to many astronomers, given the significant scientific impact of HST. The consideration that JWST will not be located in low Earth orbit, and therefore cannot be easily upgraded or repaired in the event of an early failure, only made concerns more acute. On the other hand, many astronomers felt strongly that servicing Hubble should not take place if the expense were to come from the JWST budget.

    In January 2004, O’Keefe said he would review his decision to cancel the final servicing mission to HST, due to public outcry and requests from Congress for NASA to look for a way to save it. The National Academy of Sciences convened an official panel, which recommended in July 2004 that the HST should be preserved despite the apparent risks. Their report urged “NASA should take no actions that would preclude a space shuttle servicing mission to the Hubble Space Telescope”. In August 2004, O’Keefe asked Goddard Space Flight Center to prepare a detailed proposal for a robotic service mission. These plans were later canceled, the robotic mission being described as “not feasible”. In late 2004, several Congressional members, led by Senator Barbara Mikulski, held public hearings and carried on a fight with much public support (including thousands of letters from school children across the U.S.) to get the Bush Administration and NASA to reconsider the decision to drop plans for a Hubble rescue mission.

    The nomination in April 2005 of a new NASA Administrator, Michael D. Griffin, changed the situation, as Griffin stated he would consider a crewed servicing mission. Soon after his appointment Griffin authorized Goddard to proceed with preparations for a crewed Hubble maintenance flight, saying he would make the final decision after the next two shuttle missions. In October 2006 Griffin gave the final go-ahead, and the 11-day mission by Atlantis was scheduled for October 2008. Hubble’s main data-handling unit failed in September 2008, halting all reporting of scientific data until its back-up was brought online on October 25, 2008. Since a failure of the backup unit would leave the HST helpless, the service mission was postponed to incorporate a replacement for the primary unit.

    Servicing Mission 4 (SM4), flown by Atlantis in May 2009, was the last scheduled shuttle mission for HST. SM4 installed the replacement data-handling unit, repaired the ACS and STIS systems, installed improved nickel hydrogen batteries, and replaced other components including all six gyroscopes. SM4 also installed two new observation instruments—Wide Field Camera 3 (WFC3) and the Cosmic Origins Spectrograph (COS)—and the Soft Capture and Rendezvous System, which will enable the future rendezvous, capture, and safe disposal of Hubble by either a crewed or robotic mission. Except for the ACS’s High Resolution Channel, which could not be repaired and was disabled, the work accomplished during SM4 rendered the telescope fully functional.

    Major projects

    Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey [CANDELS]

    The survey “aims to explore galactic evolution in the early Universe, and the very first seeds of cosmic structure at less than one billion years after the Big Bang.” The CANDELS project site describes the survey’s goals as the following:

    The Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey is designed to document the first third of galactic evolution from z = 8 to 1.5 via deep imaging of more than 250,000 galaxies with WFC3/IR and ACS. It will also find the first Type Ia SNe beyond z > 1.5 and establish their accuracy as standard candles for cosmology. Five premier multi-wavelength sky regions are selected; each has multi-wavelength data from Spitzer and other facilities, and has extensive spectroscopy of the brighter galaxies. The use of five widely separated fields mitigates cosmic variance and yields statistically robust and complete samples of galaxies down to 109 solar masses out to z ~ 8.

    Frontier Fields program

    The program, officially named Hubble Deep Fields Initiative 2012, is aimed to advance the knowledge of early galaxy formation by studying high-redshift galaxies in blank fields with the help of gravitational lensing to see the “faintest galaxies in the distant universe”. The Frontier Fields web page describes the goals of the program being:

    To reveal hitherto inaccessible populations of z = 5–10 galaxies that are ten to fifty times fainter intrinsically than any presently known
    To solidify our understanding of the stellar masses and star formation histories of sub-L* galaxies at the earliest times
    To provide the first statistically meaningful morphological characterization of star forming galaxies at z > 5
    To find z > 8 galaxies stretched out enough by cluster lensing to discern internal structure and/or magnified enough by cluster lensing for spectroscopic follow-up.

    Cosmic Evolution Survey (COSMOS)

    The Cosmic Evolution Survey (COSMOS) is an astronomical survey designed to probe the formation and evolution of galaxies as a function of both cosmic time (redshift) and the local galaxy environment. The survey covers a two square degree equatorial field with spectroscopy and X-ray to radio imaging by most of the major space-based telescopes and a number of large ground based telescopes, making it a key focus region of extragalactic astrophysics. COSMOS was launched in 2006 as the largest project pursued by the Hubble Space Telescope at the time, and still is the largest continuous area of sky covered for the purposes of mapping deep space in blank fields, 2.5 times the area of the moon on the sky and 17 times larger than the largest of the CANDELS regions. The COSMOS scientific collaboration that was forged from the initial COSMOS survey is the largest and longest-running extragalactic collaboration, known for its collegiality and openness. The study of galaxies in their environment can be done only with large areas of the sky, larger than a half square degree. More than two million galaxies are detected, spanning 90% of the age of the Universe. The COSMOS collaboration is led by Caitlin Casey, Jeyhan Kartaltepe, and Vernesa Smolcic and involves more than 200 scientists in a dozen countries.

    Important discoveries

    Hubble has helped resolve some long-standing problems in astronomy, while also raising new questions. Some results have required new theories to explain them.

    Age of the universe

    Among its primary mission targets was to measure distances to Cepheid variable stars more accurately than ever before, and thus constrain the value of the Hubble constant, the measure of the rate at which the universe is expanding, which is also related to its age. Before the launch of HST, estimates of the Hubble constant typically had errors of up to 50%, but Hubble measurements of Cepheid variables in the Virgo Cluster and other distant galaxy clusters provided a measured value with an accuracy of ±10%, which is consistent with other more accurate measurements made since Hubble’s launch using other techniques. The estimated age is now about 13.7 billion years, but before the Hubble Telescope, scientists predicted an age ranging from 10 to 20 billion years.

    Expansion of the universe

    While Hubble helped to refine estimates of the age of the universe, it also cast doubt on theories about its future. Astronomers from the High-z Supernova Search Team and the Supernova Cosmology Project used ground-based telescopes and HST to observe distant supernovae and uncovered evidence that, far from decelerating under the influence of gravity, the expansion of the universe may in fact be accelerating. Three members of these two groups have subsequently been awarded Nobel Prizes for their discovery.

    Saul Perlmutter [The Supernova Cosmology Project] shared the 2006 Shaw Prize in Astronomy, the 2011 Nobel Prize in Physics, and the 2015 Breakthrough Prize in Fundamental Physics with Brian P. Schmidt and Adam Riess [The High-z Supernova Search Team] for providing evidence that the expansion of the universe is accelerating.

    The cause of this acceleration remains poorly understood; the most common cause attributed is Dark Energy.

    Black holes

    The high-resolution spectra and images provided by the HST have been especially well-suited to establishing the prevalence of black holes in the center of nearby galaxies. While it had been hypothesized in the early 1960s that black holes would be found at the centers of some galaxies, and astronomers in the 1980s identified a number of good black hole candidates, work conducted with Hubble shows that black holes are probably common to the centers of all galaxies. The Hubble programs further established that the masses of the nuclear black holes and properties of the galaxies are closely related. The legacy of the Hubble programs on black holes in galaxies is thus to demonstrate a deep connection between galaxies and their central black holes.

    Extending visible wavelength images

    A unique window on the Universe enabled by Hubble are the Hubble Deep Field, Hubble Ultra-Deep Field, and Hubble Extreme Deep Field images, which used Hubble’s unmatched sensitivity at visible wavelengths to create images of small patches of sky that are the deepest ever obtained at optical wavelengths. The images reveal galaxies billions of light years away, and have generated a wealth of scientific papers, providing a new window on the early Universe. The Wide Field Camera 3 improved the view of these fields in the infrared and ultraviolet, supporting the discovery of some of the most distant objects yet discovered, such as MACS0647-JD.

    The non-standard object SCP 06F6 was discovered by the Hubble Space Telescope in February 2006.

    On March 3, 2016, researchers using Hubble data announced the discovery of the farthest known galaxy to date: GN-z11. The Hubble observations occurred on February 11, 2015, and April 3, 2015, as part of the CANDELS/GOODS-North surveys.

    Solar System discoveries

    HST has also been used to study objects in the outer reaches of the Solar System, including the dwarf planets Pluto and Eris.

    The collision of Comet Shoemaker-Levy 9 with Jupiter in 1994 was fortuitously timed for astronomers, coming just a few months after Servicing Mission 1 had restored Hubble’s optical performance. Hubble images of the planet were sharper than any taken since the passage of Voyager 2 in 1979, and were crucial in studying the dynamics of the collision of a comet with Jupiter, an event believed to occur once every few centuries.

    During June and July 2012, U.S. astronomers using Hubble discovered Styx, a tiny fifth moon orbiting Pluto.

    In March 2015, researchers announced that measurements of aurorae around Ganymede, one of Jupiter’s moons, revealed that it has a subsurface ocean. Using Hubble to study the motion of its aurorae, the researchers determined that a large saltwater ocean was helping to suppress the interaction between Jupiter’s magnetic field and that of Ganymede. The ocean is estimated to be 100 km (60 mi) deep, trapped beneath a 150 km (90 mi) ice crust.

    From June to August 2015, Hubble was used to search for a Kuiper belt object (KBO) target for the New Horizons Kuiper Belt Extended Mission (KEM) when similar searches with ground telescopes failed to find a suitable target.

    National Aeronautics Space Agency(USA)/New Horizons(US) spacecraft.

    This resulted in the discovery of at least five new KBOs, including the eventual KEM target, 486958 Arrokoth, that New Horizons performed a close fly-by of on January 1, 2019.

    In August 2020, taking advantage of a total lunar eclipse, astronomers using NASA’s Hubble Space Telescope have detected Earth’s own brand of sunscreen – ozone – in our atmosphere. This method simulates how astronomers and astrobiology researchers will search for evidence of life beyond Earth by observing potential “biosignatures” on exoplanets (planets around other stars).
    Hubble and ALMA image of MACS J1149.5+2223.

    Supernova reappearance

    On December 11, 2015, Hubble captured an image of the first-ever predicted reappearance of a supernova, dubbed “Refsdal”, which was calculated using different mass models of a galaxy cluster whose gravity is warping the supernova’s light. The supernova was previously seen in November 2014 behind galaxy cluster MACS J1149.5+2223 as part of Hubble’s Frontier Fields program. Astronomers spotted four separate images of the supernova in an arrangement known as an “Einstein Cross”.

    The light from the cluster has taken about five billion years to reach Earth, though the supernova exploded some 10 billion years ago. Based on early lens models, a fifth image was predicted to reappear by the end of 2015. The detection of Refsdal’s reappearance in December 2015 served as a unique opportunity for astronomers to test their models of how mass, especially dark matter, is distributed within this galaxy cluster.

    Impact on astronomy

    Many objective measures show the positive impact of Hubble data on astronomy. Over 15,000 papers based on Hubble data have been published in peer-reviewed journals, and countless more have appeared in conference proceedings. Looking at papers several years after their publication, about one-third of all astronomy papers have no citations, while only two percent of papers based on Hubble data have no citations. On average, a paper based on Hubble data receives about twice as many citations as papers based on non-Hubble data. Of the 200 papers published each year that receive the most citations, about 10% are based on Hubble data.

    Although the HST has clearly helped astronomical research, its financial cost has been large. A study on the relative astronomical benefits of different sizes of telescopes found that while papers based on HST data generate 15 times as many citations as a 4 m (13 ft) ground-based telescope such as the William Herschel Telescope, the HST costs about 100 times as much to build and maintain.

    Isaac Newton Group 4.2 meter William Herschel Telescope at Roque de los Muchachos Observatory | Instituto de Astrofísica de Canarias • IAC(ES) on La Palma in the Canary Islands(ES), 2,396 m (7,861 ft)

    Deciding between building ground- versus space-based telescopes is complex. Even before Hubble was launched, specialized ground-based techniques such as aperture masking interferometry had obtained higher-resolution optical and infrared images than Hubble would achieve, though restricted to targets about 108 times brighter than the faintest targets observed by Hubble. Since then, advances in “adaptive optics” have extended the high-resolution imaging capabilities of ground-based telescopes to the infrared imaging of faint objects.

    Glistening against the awesome backdrop of the night sky above ESO’s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT, a major asset of the Adaptive Optics system.

    UCO KeckLaser Guide Star Adaptive Optics on two 10 meter Keck Observatory telescopes, Maunakea Hawaii USA, altitude 4,207 m (13,802 ft).

    The usefulness of adaptive optics versus HST observations depends strongly on the particular details of the research questions being asked. In the visible bands, adaptive optics can correct only a relatively small field of view, whereas HST can conduct high-resolution optical imaging over a wide field. Only a small fraction of astronomical objects are accessible to high-resolution ground-based imaging; in contrast Hubble can perform high-resolution observations of any part of the night sky, and on objects that are extremely faint.

    Impact on aerospace engineering

    In addition to its scientific results, Hubble has also made significant contributions to aerospace engineering, in particular the performance of systems in low Earth orbit. These insights result from Hubble’s long lifetime on orbit, extensive instrumentation, and return of assemblies to the Earth where they can be studied in detail. In particular, Hubble has contributed to studies of the behavior of graphite composite structures in vacuum, optical contamination from residual gas and human servicing, radiation damage to electronics and sensors, and the long-term behavior of multi-layer insulation. One lesson learned was that gyroscopes assembled using pressurized oxygen to deliver suspension fluid were prone to failure due to electric wire corrosion. Gyroscopes are now assembled using pressurized nitrogen. Another is that optical surfaces in LEO can have surprisingly long lifetimes; Hubble was only expected to last 15 years before the mirror became unusable, but after 14 years there was no measurable degradation. Finally, Hubble servicing missions, particularly those that serviced components not designed for in-space maintenance, have contributed towards the development of new tools and techniques for on-orbit repair.

    Archives

    All Hubble data is eventually made available via the Mikulski Archive for Space Telescopes at STScI, CADC and ESA/ESAC. Data is usually proprietary—available only to the principal investigator (PI) and astronomers designated by the PI—for twelve months after being taken. The PI can apply to the director of the STScI to extend or reduce the proprietary period in some circumstances.

    Observations made on Director’s Discretionary Time are exempt from the proprietary period, and are released to the public immediately. Calibration data such as flat fields and dark frames are also publicly available straight away. All data in the archive is in the FITS format, which is suitable for astronomical analysis but not for public use. The Hubble Heritage Project processes and releases to the public a small selection of the most striking images in JPEG and TIFF formats.

    Outreach activities

    It has always been important for the Space Telescope to capture the public’s imagination, given the considerable contribution of taxpayers to its construction and operational costs. After the difficult early years when the faulty mirror severely dented Hubble’s reputation with the public, the first servicing mission allowed its rehabilitation as the corrected optics produced numerous remarkable images.

    Several initiatives have helped to keep the public informed about Hubble activities. In the United States, outreach efforts are coordinated by the Space Telescope Science Institute (STScI) Office for Public Outreach, which was established in 2000 to ensure that U.S. taxpayers saw the benefits of their investment in the space telescope program. To that end, STScI operates the HubbleSite.org website. The Hubble Heritage Project, operating out of the STScI, provides the public with high-quality images of the most interesting and striking objects observed. The Heritage team is composed of amateur and professional astronomers, as well as people with backgrounds outside astronomy, and emphasizes the aesthetic nature of Hubble images. The Heritage Project is granted a small amount of time to observe objects which, for scientific reasons, may not have images taken at enough wavelengths to construct a full-color image.

    Since 1999, the leading Hubble outreach group in Europe has been the Hubble European Space Agency Information Centre (HEIC). This office was established at the Space Telescope European Coordinating Facility in Munich, Germany. HEIC’s mission is to fulfill HST outreach and education tasks for the European Space Agency. The work is centered on the production of news and photo releases that highlight interesting Hubble results and images. These are often European in origin, and so increase awareness of both ESA’s Hubble share (15%) and the contribution of European scientists to the observatory. ESA produces educational material, including a videocast series called Hubblecast designed to share world-class scientific news with the public.

    The Hubble Space Telescope has won two Space Achievement Awards from the Space Foundation, for its outreach activities, in 2001 and 2010.

    A replica of the Hubble Space Telescope is on the courthouse lawn in Marshfield, Missouri, the hometown of namesake Edwin P. Hubble.

    Major Instrumentation

    Hubble WFPC2 no longer in service.

    Wide Field Camera 3 [WFC3]

    National Aeronautics Space Agency(USA)/The European Space Agency [La Agencia Espacial Europea] [Agence spatiale européenne][Europäische Weltraumorganisation](EU) Hubble Wide Field Camera 3

    Advanced Camera for Surveys [ACS]

    National Aeronautics Space Agency(US)/European Space Agency [La Agencia Espacial Europea] [Agence spatiale européenne][Europäische Weltraumorganisation](EU) NASA/ESA Hubble Space Telescope(US) Advanced Camera for Surveys

    Cosmic Origins Spectrograph [COS]

    National Aeronautics Space Agency (US) Cosmic Origins Spectrograph.

    The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI), is a free-standing science center, located on the campus of The Johns Hopkins University and operated by the Association of Universities for Research in Astronomy (AURA) for NASA, conducts Hubble science operations.

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  • richardmitnick 4:34 pm on December 19, 2021 Permalink | Reply
    Tags: "A long time ago in a galaxy far far away..." ["StarWars" LucasFilm], "Unfolding the heavens", Ancient visible light has been stretched to longer infrared wavelengths on its journey to us., , , , , , , Ground based Optical/Infrared Astronomy, Infrared light is not blocked by the thick giant clouds of dust wandering in space., JWST will admire some of the very first stars and galaxies in the history of the cosmos., LaGrange Points- five points of equilibrium of gravity between the Sun and Earth., , , Unfolding a telescope; unfolding the Universe   

    From ESOblog (EU): “Unfolding the heavens” 

    From ESOblog (EU)

    At

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    European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU) (CL)

    17 December 2021
    Science@ESO

    National Aeronautics Space Agency(USA)/European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU)/ Canadian Space Agency [Agence Spatiale Canadienne](CA) Webb Infrared Space Telescope(US) James Webb Space Telescope annotated. Scheduled for launch in October 2021 delayed to December 2021.

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    Giulio Mazzolo.
    Giulio Mazzolo is a science journalism intern at ESO. Before starting a career in science communication, he completed a PhD in astrophysics from The MPG Institute for Gravitational Physics [MPG Institut für Gravitationsphysik] (Albert Einstein Institute) (DE) and has been a member of the LIGO Scientific Collaboration (US).

    Soon the James Webb Space Telescope (JWST) will be launched into space [ten years late], and astronomers could not ask for a better present! Built by The National Aeronautics and Space Administration (US), The European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU) and The Canadian Space Agency [Agence spatiale canadienne, ASC](CA), it will be the largest and most powerful space observatory ever created, scanning the heavens all the way back to the very first stars in the history of the Universe. But how does it work? Which cosmic secrets will it unlock? And how will it join forces with other astronomical Goliaths like ESO’s Extremely Large Telescope [below]?

    Given all the breakthrough discoveries made in the last years, this truly is a golden age for astronomy; an age about to get even brighter with the beginning of JWST’s adventure.

    Unfolding a telescope; unfolding the Universe

    JWST is the result of more than two decades of work by thousands of scientists and engineers located in 14 countries, with astronomers from 41 countries having been awarded observing time during the first year of science operations. A really international endeavour spanning the whole globe!

    It will build upon its illustrious forebears, the NASA/ESA Hubble Space Telescope and NASA’s Spitzer Space Telescope, and it will probe the cosmos in the infrared.

    National Aeronautics and Space Administration(US)/European Space Agency [Agence spatiale européenne] [Europäische Weltraumorganisation](EU) Hubble Space Telescope.

    National Aeronautics and Space Administration(US) Spitzer Infrared Space Telescope no longer in service. Launched in 2003 and retired on 30 January 2020.

    This brings two main benefits: first, infrared light is not blocked by the thick, giant clouds of dust wandering in space. This allows astronomers to see the cosmic objects behind the clouds which would otherwise remain hidden in visible light. Second, it will enable JWST to admire some of the very first stars and galaxies in the history of the cosmos. This is because the universe is expanding, meaning their ancient visible light has been stretched to longer infrared wavelengths on its journey to us.

    As heavy as a school bus once launched JWST will be travelling for one month to the so-called second Lagrange point (L2) of the Sun-Earth system.

    LaGrange Points map. NASA.

    Being at L2 will allow JWST to keep its massive sunshield, as large as a tennis court, permanently oriented towards the Sun and the Earth, blocking their radiation. The telescope needs to be kept at an extremely cold temperature of -230 ºC, otherwise the thermal radiation from the telescope itself would blind the astronomical observations at infrared wavelengths.

    JWST’s primary mirror is 6.5-metres wide and is segmented into 18 hexagonal pieces.These segments are made of beryllium and covered in a layer of gold to optimise the reflection of incoming infrared light. The gold layer is extremely thin: only about 700 atoms, for an amount of gold of just 48 grams for the entire mirror!

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    The primary mirror of JWST, in its unfolded configuration, being lifted and moved into a clean room at NASA´s Goddard Space Flight Center. Credit: Desiree Stover/NASA.

    To fit such a huge telescope in the Ariane 5 rocket that will launch it into space, JWST was cleverly designed to be folded. Once in space, the sunshield and mirror will unfold in a complex origami manoeuvre.

    Later this decade, JWST will be joined in its mission to unravel the cosmos by ESO’s Extremely Large Telescope (ELT), currently under construction in Chile’s Atacama Desert, and which will also be active in the infrared. With its 39 meter mirror, ESO’s ELT will be the world’s biggest eye on the Universe, promising to deepen our understanding of the heavens.

    The ELT and JWST will nicely complement each other. Being in space will allow JWST to be extremely sensitive at infrared wavelengths, and it won’t have to worry about the blurring caused by atmospheric turbulence. The ELT, on the other hand, has a much larger mirror, and after correcting atmospheric turbulence with Adaptive Optics [below] it will be able to obtain even sharper images. One drawback of JWST being at L2 is that upgrades won’t be possible, which is not an issue for the ELT. Both telescopes carry a suite of sophisticated instruments that will tackle similar problems in a complementary way, and astronomers are already rubbing their hands. Let’s see why.

    Let there be light

    No planets, no stars, no galaxies. Just a mist of hydrogen and helium gas and, possibly, dark matter. At the beginning of its so-called Cosmic Dark Ages, approximately 400 000 years after the Big Bang, the Universe must have been a pretty boring place to visit. Until the first stars started lighting up here and there.

    We think those first stars were massive beasts — from a few tens to several hundreds of times our Sun. They were living a fast and furious lifestyle, only surviving for a few million years during which they emitted intense high-energy radiation, before exploding as supernovae. Relentlessly, this energetic radiation stripped the surrounding hydrogen and helium from their electrons, the so-called Epic of Reionization.

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    Universe. Atacama Large Millimiter/submillimeter Array (CL) [ALMA] 300000 Years After the Big Bang Credit: National Astronomical Observatory of Japan[国立天文台](JP).

    But dark ages are hard to come out of, and the cosmic one was no exception. Reionization did not happen overnight all over the Universe. Most likely, it started in cosmic bubbles scattered here and there. Where were these first pockets and how big were they? How did reionisation extend throughout the whole Universe? How exactly did the first stars look?

    We do not know the answer…yet, as ESO’s ELT and JWST will push back the limits of what we can currently observe, back to the edge of the dark ages, unveiling how and when light in the Universe was switched on.

    A long time ago, in a galaxy far, far away…

    The stars born during the dark ages came together to form the first galaxies populating the cosmos. These ancient galaxies were probably rather small and irregularly shaped. Over time, they merged into each other, leading to larger, more structured galaxies. But how exactly this happened is still unknown.

    ESO’s ELT and JWST will be able to study galaxies all over the history of the cosmos, analysing their shapes, chemical composition and at what rate they form stars. In their search, they will be helped by radio telescopes such as the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile [below], in which ESO is a partner, which maps the distribution of the cold gas out of which stars form.

    By comparing galaxies across different cosmic eras, astronomers will be able to draw a picture of how they form and evolve.

    Strongly related with the study of galaxies is the investigation of the intergalactic medium — the matter in the space between galaxies.


    Intergalactic medium. Credit: Princeton University (US).

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    Intergalactic medium. The structure of the intergalactic medium can be illustrated by the Millenium simulation. Millennium Simulation Project [MPG Institute for Astrophysics [Max-Planck-Institut für Astrophysik]](DE).

    Believed to make up most of the visible matter in the Universe, it is the descendant of the mist of hydrogen and helium from the dark ages. Little is known about it, but astronomers are aware of its interplay with galaxies. On one hand, the intergalactic medium can feed galaxies with pristine gas, fueling the birth of new stars. On the other hand, galaxies can influence the properties of the intergalactic medium through the energy and gas they expel into it. ESO’s ELT and JWST will allow the intergalactic medium to be mapped to the distant corners of the Universe, shedding new light on its nature.

    Another problem that these two telescopes will tackle is the nature of Dark Matter and Dark Energy, which still cause astronomers to scratch their heads.
    ______________________________________________________
    Dark Matter Background
    Fritz Zwicky discovered Dark Matter in the 1930s when observing the movement of the Coma Cluster., Vera Rubin a Woman in STEM, denied the Nobel, some 30 years later, did most of the work on Dark Matter.

    Fritz Zwicky.

    Coma cluster via NASA/ESA Hubble, the original example of Dark Matter discovered during observations by Fritz Zwicky and confirmed 30 years later by Vera Rubin.

    In modern times, it was astronomer Fritz Zwicky, in the 1930s, who made the first observations of what we now call dark matter. His 1933 observations of the Coma Cluster of galaxies seemed to indicated it has a mass 500 times more than that previously calculated by Edwin Hubble. Furthermore, this extra mass seemed to be completely invisible. Although Zwicky’s observations were initially met with much skepticism, they were later confirmed by other groups of astronomers.

    Thirty years later, astronomer Vera Rubin provided a huge piece of evidence for the existence of dark matter. She discovered that the centers of galaxies rotate at the same speed as their extremities, whereas, of course, they should rotate faster. Think of a vinyl LP on a record deck: its center rotates faster than its edge. That’s what logic dictates we should see in galaxies too. But we do not. The only way to explain this is if the whole galaxy is only the center of some much larger structure, as if it is only the label on the LP so to speak, causing the galaxy to have a consistent rotation speed from center to edge.

    Vera Rubin, following Zwicky, postulated that the missing structure in galaxies is dark matter. Her ideas were met with much resistance from the astronomical community, but her observations have been confirmed and are seen today as pivotal proof of the existence of dark matter.

    Astronomer Vera Rubin at the Lowell Observatory in 1965, worked on Dark Matter (The Carnegie Institution for Science).

    Vera Rubin, with Department of Terrestrial Magnetism (DTM) image tube spectrograph attached to the Kitt Peak 84-inch telescope, 1970.

    Vera Rubin measuring spectra, worked on Dark Matter(Emilio Segre Visual Archives AIP SPL).

    Dark Matter Research

    LBNL LZ Dark Matter Experiment (US) xenon detector at Sanford Underground Research Facility(US) Credit: Matt Kapust.

    Lamda Cold Dark Matter Accerated Expansion of The universe http scinotions.com the-cosmic-inflation-suggests-the-existence-of-parallel-universes. Credit: Alex Mittelmann.

    DAMA at Gran Sasso uses sodium iodide housed in copper to hunt for dark matter LNGS-INFN.

    Yale HAYSTAC axion dark matter experiment at Yale’s Wright Lab.

    DEAP Dark Matter detector, The DEAP-3600, suspended in the SNOLAB (CA) deep in Sudbury’s Creighton Mine.

    The LBNL LZ Dark Matter Experiment (US) Dark Matter project at SURF, Lead, SD, USA.

    DAMA-LIBRA Dark Matter experiment at the Italian National Institute for Nuclear Physics’ (INFN’s) Gran Sasso National Laboratories (LNGS) located in the Abruzzo region of central Italy.

    DARWIN Dark Matter experiment. A design study for a next-generation, multi-ton dark matter detector in Europe at The University of Zurich [Universität Zürich](CH).

    PandaX II Dark Matter experiment at Jin-ping Underground Laboratory (CJPL) in Sichuan, China.

    Inside the Axion Dark Matter eXperiment U Washington (US) Credit : Mark Stone U. of Washington. Axion Dark Matter Experiment.
    _____________________________________________________________________________________
    Dark Energy Survey

    Dark Energy Camera [DECam] built at DOE’s Fermi National Accelerator Laboratory(US).

    NOIRLab National Optical Astronomy Observatory(US) Cerro Tololo Inter-American Observatory(CL) Victor M Blanco 4m Telescope which houses the Dark-Energy-Camera – DECam at Cerro Tololo, Chile at an altitude of 7200 feet.

    NOIRLab(US)NSF NOIRLab NOAO (US) Cerro Tololo Inter-American Observatory(CL) approximately 80 km to the East of La Serena, Chile, at an altitude of 2200 meters.

    Timeline of the Inflationary Universe WMAP.

    The Dark Energy Survey (DES) is an international, collaborative effort to map hundreds of millions of galaxies, detect thousands of supernovae, and find patterns of cosmic structure that will reveal the nature of the mysterious dark energy that is accelerating the expansion of our Universe. DES began searching the Southern skies on August 31, 2013.

    According to Einstein’s theory of General Relativity, gravity should lead to a slowing of the cosmic expansion. Yet, in 1998, two teams of astronomers studying distant supernovae made the remarkable discovery that the expansion of the universe is speeding up. To explain cosmic acceleration, cosmologists are faced with two possibilities: either 70% of the universe exists in an exotic form, now called dark energy, that exhibits a gravitational force opposite to the attractive gravity of ordinary matter, or General Relativity must be replaced by a new theory of gravity on cosmic scales.

    DES is designed to probe the origin of the accelerating universe and help uncover the nature of dark energy by measuring the 14-billion-year history of cosmic expansion with high precision. More than 400 scientists from over 25 institutions in the United States, Spain, the United Kingdom, Brazil, Germany, Switzerland, and Australia are working on the project. The collaboration built and is using an extremely sensitive 570-Megapixel digital camera, DECam, mounted on the Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory, high in the Chilean Andes, to carry out the project.

    Over six years (2013-2019), the DES collaboration used 758 nights of observation to carry out a deep, wide-area survey to record information from 300 million galaxies that are billions of light-years from Earth. The survey imaged 5000 square degrees of the southern sky in five optical filters to obtain detailed information about each galaxy. A fraction of the survey time is used to observe smaller patches of sky roughly once a week to discover and study thousands of supernovae and other astrophysical transients.
    _____________________________________________________________________________________

    Dark matter is believed to be distributed all over the cosmos, forming huge halos around galaxies. Without it, and given our current understanding of gravity, it’s hard to explain the large scale structure of the universe and why galaxies spin the way they do. Dark energy, on the other hand, is thought to cause the accelerated expansion of the Universe. Through the detailed analysis of galaxies at different distances, astronomers hope to finally break the code of these two enigmas of the cosmos.

    We are all made of stardust

    The life cycle of stars is another hot topic in astronomy. That’s quite understandable considering the building blocks of literally everyone on this planet — including you — are forged in stars.

    Stars form in massive clouds of gas and dust. These clouds are transparent to infrared light, which the ELT and JWST will use to gaze into them with unprecedented detail, opening a new window on how stars and planets form and develop.

    In addition to baby stars, the two telescopes will also investigate more mature ones, both in the Milky Way and beyond, as their chemical compositions and motions tell the story of how their host galaxies were assembled.

    And then, just like us humans, stars will eventually die. Low-mass stars die quietly, whereas massive ones end with huge supernova explosions. Studying supernovae with JWST and ESO’s ELT will allow us not only to understand how these explosions occur, but also how the elements forged in the stars are expelled into the Universe to one day form new stars, planets and, possibly, living beings.

    The most massive supernovae are also one of the sources of high-energy radiation flashes known as gamma-ray bursts [GRB’s], the most energetic events in the Universe. The ELT and JWST will be able to spot them across most epochs in the history of the Universe, using them as powerful beacons to go all the way back to the end of the dark ages.

    The world is not enough

    The Earth is just one of billions of planets out there in the Universe. How the Solar System formed and whether there is life somewhere else in the Universe are two of the deepest questions humanity has ever pondered. Searching for other planets [exoplanets] and studying the thousands we already know are the only way to find the answer.

    4
    The European Southern Observatory’s Very Large Telescope (ESO’s VLT) [below] has captured an image of a planet orbiting b Centauri-a two-star system that can be seen with the naked eye. This is the hottest and most massive planet-hosting star system found to date, and the planet was spotted orbiting it at 100 times the distance Jupiter orbits the Sun. Some astronomers believed planets could not exist around stars this massive and this hot — until now.
    ===
    To find unknown worlds, ESO’s ELT will be a formidable ace up astronomers’ sleeve. It will use the so-called radial velocity method — basically, inferring the presence of a planet from how its gravitational pull influences the motion of the parent star — with unprecedented accuracy.

    Radial Velocity Method-Las Cumbres Observatory, a network of astronomical observatories, located at both northern and southern hemisphere sites distributed in longitude around the Earth.

    Radial velocity Image via SuperWasp.

    This will help us to spot many new rocky planets, like the Earth or Mars. These are much smaller than gas giants — such as Jupiter — and, hence, more difficult to find due to the weaker gravitational effect on the star’s motion. Rocky planets, when placed at the right distance from their star to host liquid water on the surface, are the most likely candidates to host life as we know it.

    The ELT will also be able to directly image alien worlds. A challenging feat, as planets are often outshone by their parent star — and this is why such observations are typically done in the infrared, where the difference in brightness between the planet and the star is milder. But a necessary one to characterise the physical properties of the planet, such as mass and size.

    The next step after discovering a planet is to study its atmosphere. To understand which molecules make it up, astronomers peer at the planet when it passes between us and the star. This way, the light from the star reaches us after crossing the atmosphere and by checking which wavelengths have been absorbed, researchers can determine its composition. The ELT and JWST will excel in this and may be the first to find traces of life outside the Earth.

    ESO’s ELT and JWST will not only study mature planets, but also unlock the secrets of worlds still in the process of forming. They will look at the so-called protoplanetary discs around newly born stars, from which planetary systems emerge. Thanks to their unprecedented accuracy, they will be able to probe the inner regions of these gaseous structures, where rocky planets form, beautifully complementing observations of the colder, outer regions home to gas giants done with radio telescopes such as ALMA.

    Of course, the ELT and JWST will not overlook our neighbours within the Solar System. They will use their powerful eyes to probe the surface and atmosphere of planets, moons, comets and asteroids, giving us a new perspective on our home planetary system.

    After all, sometimes in life answers could be much closer than we think.

    See the full article here .


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    European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU) is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    European Southern Observatory(EU) La Silla HELIOS (HARPS Experiment for Light Integrated Over the Sun).

    ESO 3.6m telescope & HARPS atCerro LaSilla, Chile, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    MPG Institute for Astronomy [Max-Planck-Institut für Astronomie](DE) 2.2 meter telescope at/European Southern Observatory(EU) Cerro La Silla, Chile, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    European Southern Observatory(EU)La Silla Observatory 600 km north of Santiago de Chile at an altitude of 2400 metres.

    European Southern Observatory(EU) , Very Large Telescope at Cerro Paranal in the Atacama Desert •ANTU (UT1; The Sun ) •KUEYEN (UT2; The Moon ) •MELIPAL (UT3; The Southern Cross ), and •YEPUN (UT4; Venus – as evening star). Elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo.

    European Southern Observatory(EU)VLTI Interferometer image, Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level, •ANTU (UT1; The Sun ),
    •KUEYEN (UT2; The Moon ),
    •MELIPAL (UT3; The Southern Cross ), and
    •YEPUN (UT4; Venus – as evening.

    ESO Very Large Telescope 4 lasers on Yepun (CL)

    Glistening against the awesome backdrop of the night sky above ESO’s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT, a major asset of the Adaptive Optics system.

    ESO/NTT NTT at Cerro La Silla , Chile, at an altitude of 2400 metres.

    Part of ESO’s Paranal Observatory, the VLT Survey Telescope (VISTA) observes the brilliantly clear skies above the Atacama Desert of Chile. It is the largest survey telescope in the world in visible light, with an elevation of 2,635 metres (8,645 ft) above sea level.

    European Southern Observatory/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

    European Southern Observatory(EU) ELT 39 meter telescope to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).

    European Southern Observatory(EU)/MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie](DE) ESO’s Atacama Pathfinder Experiment(CL) high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft).

    Leiden MASCARA instrument cabinet at Cerro La Silla, located in the southern Atacama Desert 600 kilometres (370 mi) north of Santiago de Chile at an altitude of 2,400 metres (7,900 ft).

    ESO Next Generation Transit Survey telescopes, an array of twelve robotic 20-centimetre telescopes at Cerro Paranal,(CL) 2,635 metres (8,645 ft) above sea level.

    ESO Speculoos telescopes four 1 meter robotic telescopes at ESO Paranal Observatory 2635 metres 8645 ft above sea level.

    TAROT telescope at Cerro LaSilla, 2,635 metres (8,645 ft) above sea level.

    European Southern Observatory(EU) ExTrA telescopes at erro LaSilla at an altitude of 2400 metres.

    A novel gamma ray telescope under construction on Mount Hopkins, Arizona. A large project known as the Čerenkov Telescope Array composed of hundreds of similar telescopes to be situated in the Canary Islands and Chile at, ESO Cerro Paranal site The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the. University of Wisconsin–Madison and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev.

    European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU), The new Test-Bed Telescope 2is housed inside the shiny white dome shown in this picture, at ESO’s LaSilla Facility in Chile. The telescope has now started operations and will assist its northern-hemisphere twin in protecting us from potentially hazardous, near-Earth objects.The domes of ESO’s 0.5 m and the Danish 0.5 m telescopes are visible in the background of this image.Part of the world-wide effort to scan and identify near-Earth objects, the European Space Agency’s Test-Bed Telescope 2 (TBT2), a technology demonstrator hosted at ESO’s La Silla Observatory in Chile, has now started operating. Working alongside its northern-hemisphere partner telescope, TBT2 will keep a close eye on the sky for asteroids that could pose a risk to Earth, testing hardware and software for a future telescope network.

    European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU) The open dome of The black telescope structure of the‘s Test-Bed Telescope 2 peers out of its open dome in front of the rolling desert landscape. The telescope is located at ESO’s La Silla Observatory, which sits at a 2400 metre altitude in the Chilean Atacama desert.a desert.

     
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