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  • richardmitnick 9:19 pm on August 29, 2019 Permalink | Reply
    Tags: , , ‘Alopeke/Zorro, , , , Gemini Observatory   

    From Gemini Observatory: “Exoplanets Can’t Hide Their Secrets from Innovative New Instrument” 

    NOAO

    Gemini Observatory
    From Gemini Observatory

    August 29, 2019

    Media Contacts:

    Peter Michaud
    Public Information and Outreach Manager
    Gemini Observatory, Hilo, HI
    email: pmichaud”at”gemini.edu
    Desk: (808) 974-2510
    Cell: (808) 936-6643

    Alyssa Grace
    Public Information and Outreach Assistant
    Gemini Observatory, Hilo, HI
    email: agrace”at”gemini.edu
    Desk: (808) 974-2531

    Science Contacts:

    Steve B. Howell
    Space Science and Astrobiology Division
    NASA Ames Research Center, Moffett Field, CA
    email: steve.b.howell”at”nasa.gov
    Desk: (650) 604-4238
    Cell: (520) 461-6925

    Andrew Stephens
    Instrument Scientist
    Gemini Observatory, Hilo, HI
    email: astephens”at”gemini.edu
    Desk: (808) 974-2611

    In an unprecedented feat, an American research team discovered hidden secrets of an elusive exoplanet using a powerful new instrument at the 8-meter Gemini North telescope on Maunakea in Hawai‘i [below]. The findings not only classify a Jupiter-sized exoplanet in a close binary star system, but also conclusively demonstrate, for the first time, which star the planet orbits.

    The breakthrough occurred when Steve B. Howell of the NASA Ames Research Center and his team used a high-resolution imaging instrument of their design — named ‘Alopeke (a contemporary Hawaiian word for Fox).

    2
    ‘Alopeke at Gemini North

    The team observed exoplanet Kepler-13b as it passed in front of (transited) one of the stars in the Kepler-13AB binary star system some 2,000 light years distant. Prior to this attempt, the true nature of the exoplanet was a mystery.

    3
    Artist’s conception of the Kepler-13AB binary star system as revealed by observations including the new Gemini Observatory data. The two stars (A and B) are large, massive bluish stars (center) with the transiting “hot Jupiter” (Kepler-13b) in the foreground (left corner). Star B and its low mass red dwarf companion star are seen in the background to the right. Credit: Gemini Observatory/NSF/AURA/Artwork by Joy Pollard

    “There was confusion over Kepler-13b: was it a low-mass star or a hot Jupiter-like world? So we devised an experiment using the sly instrument ‘Alopeke,” Howell said. The research was recently published in The Astronomical Journal. “We monitored both stars, Kepler A and Kepler B, simultaneously while looking for any changes in brightness during the planet’s transit,” Howell explained. “To our pleasure, we not only solved the mystery, but also opened a window into a new era of exoplanet research.”

    “This dual win has elevated the importance of instruments like ‘Alopeke in exoplanet research,” said Chris Davis of the National Science Foundation, one of Gemini’s sponsoring agencies. “The exquisite seeing and telescope abilities of Gemini Observatory, as well as the innovative ‘Alopeke instrument made this discovery possible in merely four hours of observations.”

    ‘Alopeke performs “speckle imaging,” collecting a thousand 60-millisecond exposures every minute. After processing this large amount of data, the final images are free of the adverse effects of atmospheric turbulence — which can bloat, blur, and distort star images.

    “About one half of all exoplanets orbit a star residing in a binary system, yet, until now, we were at a loss to robustly determine which star hosts the planet,” said Howell.

    The team’s analysis revealed a clear drop in the light from Kepler A, proving that the planet orbits the brighter of the two stars. Moreover, ‘Alopeke simultaneously provides data at both red and blue wavelengths, an unusual capability for speckle imagers. Comparing the red and blue data, the researchers were surprised to discover that the dip in the star’s blue light was about twice as deep as the dip seen in red light. This can be explained by a hot exoplanet with a very extended atmosphere, which more effectively blocks the light at blue wavelengths. Thus, these multi-color speckle observations give a tantalizing glimpse into the appearance of this distant world.

    Early observations once pointed to the transiting object being either a low-mass star or a brown dwarf (an object somewhere between the heaviest planets and the lightest stars). But Howell and his team’s research almost certainly shows the object to be a Jupiter-like gas-giant exoplanet with a “puffed up” atmosphere due to exposure to the tremendous radiation from its host star.

    ‘Alopeke has an identical twin at the Gemini South telescope in Chile [below], named Zorro, which is the word for fox in Spanish. Like ‘Alopeke, Zorro is capable of speckle imaging in both blue and red wavelengths. The presence of these instruments in both hemispheres allows Gemini Observatory to resolve the thousands of exoplanets known to be in multiple star systems.

    “Speckle imaging is experiencing a renaissance with technology like fast, low noise detectors becoming more easily available,” said team member and ‘Alopeke instrument scientist Andrew Stephens at the Gemini North telescope. “Combined with Gemini’s large primary mirror, ‘Alopeke has real potential to make even more significant exoplanet discoveries by adding another dimension to the search.”

    First proposed by French astronomer Antoine Labeyrie in 1970, speckle imaging is based on the idea that atmospheric turbulence can be “frozen” when obtaining very short exposures. In these short exposures, stars look like collections of little spots, or speckles, where each of these speckles has the size of the telescope’s optimal limit of resolution. When taking many exposures, and using a clever mathematical approach, these speckles can be reconstructed to form the true image of the source, removing the effect of atmospheric turbulence. The result is the highest-quality image that a telescope can produce, effectively obtaining space-based resolution from the ground — making these instruments superb probes of extrasolar environments that may harbor planets.

    The discovery of planets orbiting other stars has changed the view of our place in the Universe. Space missions like NASA’s Kepler/K2 Space Telescope and the Transiting Exoplanet Survey Satellite (TESS) have revealed that there are twice as many planets orbiting stars in the sky than there are stars visible to the unaided eyes; to date the total discovery count hovers around 4,000. While these telescopes detect exoplanets by looking for tiny dips in the brightness of a star when a planet crosses in front of it, they have their limits.

    NASA/Kepler Telescope, and K2 March 7, 2009 until November 15, 2018

    NASA/MIT TESS replaced Kepler in search for exoplanets

    “These missions observe large fields of view containing hundreds of thousands of stars, so they don’t have the fine spatial resolution necessary to probe deeper,” Howell said. “One of the major discoveries of exoplanet research is that about one-half of all exoplanets orbit stars that reside in binary systems. Making sense of these complex systems requires technologies that can conduct time sensitive observations and investigate the finer details with exceptional clarity.”

    “Our work with Kepler-13b stands as a model for future research of exoplanets in multiple star systems,” Howell continued. “The observations highlight the ability of high-resolution imaging with powerful telescopes like Gemini to not only assess which stars with planets are in binaries, but also robustly determine which of the stars the exoplanet orbits.”

    See the full article here .


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    Please help promote STEM in your local schools.


    Stem Education Coalition

    NOAO Gemini North on MaunaKea, Hawaii, USA, Altitude 4,213 m (13,822 ft)


    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet


    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 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.

     
  • richardmitnick 3:11 pm on August 22, 2019 Permalink | Reply
    Tags: "Revealing the Intimate Lives of MASSIVE Galaxies", , , , , Gemini Observatory   

    From Gemini Observatory: “Revealing the Intimate Lives of MASSIVE Galaxies” 

    NOAO

    Gemini Observatory
    From Gemini Observatory

    August 22, 2019

    Every galaxy has a story, and every galaxy has been many others in the past (unlike for humans, this is not purely metaphorical, as galaxies grow via hierarchical assembly). Generally speaking, the most massive galaxies have led the most interesting lives, often within teeming galactic metropolises where they are subject to frequent interactions with assorted neighbors. These interactions influence the structure and motions of the stars, gas, and dark matter that make up the galaxies. They also affect the growth of the supermassive black holes at the galaxies’ centers.

    Although the detailed life stories of most galaxies will remain forever uncertain, the key thematic elements may be surmised in various ways. A particularly powerful probe of a galaxy’s dynamical structure is called integral field spectroscopy (IFS), which dissects a galaxy’s light at each point within the spectrograph’s field of view. In this way, it is possible to construct a map of the motions of the stars within the galaxy and infer the distribution of the mass, both visible and invisible. IFS observations of the outskirts of a galaxy can provide insight into its global dynamics and past interactions, while IFS data on the innermost region can measure the mass of the supermassive black hole and the motions of the stars in its vicinity.

    The MASSIVE Galaxy Survey, led by Chung-Pei Ma of the University of California, Berkeley, is a major effort to uncover the internal structures and formation histories of the most massive galaxies within 350 million light years of our Milky Way. A recent study by the MASSIVE team presents high angular resolution IFS observations of 20 high-mass galaxies obtained with GMOS at Gemini North, combined with wide-field IFS data on the same galaxies from the 2.7-meter Harlan J Smith 2.7-meter Telescope telescope at McDonald Observatory in Texas.

    GEMINI/North GMOS

    NOAO Gemini North on MaunaKea, Hawaii, USA, Altitude 4,213 m (13,822 ft)

    U Texas at Austin McDonald Observatory Harlan J Smith 2.7-meter Telescope , Altitude 2,026 m (6,647 ft)

    The study, led by Berkeley graduate student Irina Ene, appears in the June issue of The Astrophysical Journal.

    The accompanying figure shows example maps of four indicators, or “moments” (called v, σ, h3 , and h4), of the stellar motions within two galaxies in the MASSIVE survey. The maps, based on the GMOS IFS data, cover the central regions of the galaxies. The figure also shows graphs of how these indicators vary with distance from the centers of these galaxies. Although both galaxies exhibit ordered central rotation, they are strikingly different in how the motions of the stars vary within the galaxy. Interestingly, for galaxies in the MASSIVE Survey, the directions of the motions of the stars in the central regions are often unaligned with the motions at large radius. This indicates complex and diverse merger histories.

    3
    Figure caption. Example distributions of the first four velocity “moments” (called v, σ, h3 and h4 ) measured from the GMOS-N IFS data for two of the MASSIVE survey galaxies. For each galaxy, the top row shows two-dimensional maps, while the bottom row shows two-sided radial profiles from Gemini/GMOS-N (magenta circles) and McDonald Observatory (green squares) data. For more information, see the study by Berkeley graduate student Irina Ene.

    As a proof of concept, the new study performs detailed dynamical modeling of the IFS data for NGC 1453, the galaxy in the sample with the fastest rotation rate. The team’s analysis reveals the amount of dark matter in this galaxy and shows how the shapes of the stars’ orbits change with radius. In addition, the team found an impressively large mass for the central black hole, more than three billion times the mass of our Sun. The MASSIVE Survey team is currently performing detailed modeling for all the rest of the galaxies in the sample. The results will provide further insight into the assembly histories of the largest galaxies in the local Universe and refine our understanding of the coevolution of galaxies and their central black holes up to the most extreme masses.

    See the full article here .


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    Please help promote STEM in your local schools.


    Stem Education Coalition

    NOAO Gemini North on MaunaKea, Hawaii, USA, Altitude 4,213 m (13,822 ft)


    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet


    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 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.

     
  • richardmitnick 1:11 pm on August 6, 2019 Permalink | Reply
    Tags: , Astronomical geology, , , , , Gemini Observatory, The Jupiter Moon Io and its vulcanism   

    From Gemini Observatory: “Discovering Patterns in Io’s Volcanoes” 

    NOAO

    Gemini Observatory
    From Gemini Observatory

    August 5, 2019

    1
    Orbital Resonnances of the Galilean Moons of Jupiter. Animation of the 1:2:4 Laplace resonance between Ganymede, Europa, and Io. The labels indicate the ratios of orbital periods: Europa’s is twice Io’s, and Ganymede’s is four times Io’s. Credit: Matma Rex/Wikicommons.

    Jupiter’s volcanic moon Io brought astronomers and geologists together to reveal that this moon’s hot spots fluctuate on unexpected timescales.

    4
    NASA’s Galileo spacecraft acquired its highest resolution images of Jupiter’s moon Io on 3 July 1999 during its closest pass to Io since orbit insertion in late 1995. This color mosaic uses the near-infrared, green and violet filters (slightly more than the visible range) of the spacecraft’s camera and approximates what the human eye would see. Most of Io’s surface has pastel colors, punctuated by black, brown, green, orange, and red units near the active volcanic centers. A false color version of the mosaic has been created to enhance the contrast of the color variations.

    The improved resolution reveals small-scale color units which had not been recognized previously and which suggest that the lavas and sulfurous deposits are composed of complex mixtures (Cutout A of false color image). Some of the bright (whitish), high-latitude (near the top and bottom) deposits have an ethereal quality like a transparent covering of frost (Cutout B of false color image). Bright red areas were seen previously only as diffuse deposits. However, they are now seen to exist as both diffuse deposits and sharp linear features like fissures (Cutout C of false color image). Some volcanic centers have bright and colorful flows, perhaps due to flows of sulfur rather than silicate lava (Cutout D of false color image). In this region bright, white material can also be seen to emanate from linear rifts and cliffs.

    Comparison of this image to previous Galileo images reveals many changes due to the ongoing volcanic activity.

    Galileo will make two close passes of Io beginning in October of this year. Most of the high-resolution targets for these flybys are seen on the hemisphere shown here.

    North is to the top of the picture and the sun illuminates the surface from almost directly behind the spacecraft. This illumination geometry is good for imaging color variations, but poor for imaging topographic shading. However, some topographic shading can be seen here due to the combination of relatively high resolution (1.3 kilometers or 0.8 miles per picture element) and the rugged topography over parts of Io. The image is centered at 0.3 degrees north latitude and 137.5 degrees west longitude. The resolution is 1.3 kilometers (0.8 miles) per picture element. The images were taken on 3 July 1999 at a range of about 130,000 kilometers (81,000 miles) by the Solid State Imaging (SSI) system on NASA’s Galileo spacecraft during its twenty-first orbit.

    The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA’s Office of Space Science, Washington, DC.
    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo.

    The team utilized the Gemini North telescope [below] and the W.M. Keck Observatory, both located on Maunakea, Hawaiʻi Island.

    Keck Observatory, operated by Caltech and the University of California, Maunakea Hawaii USA, 4,207 m (13,802 ft)

    The Gemini observations, which provided about 80% of the data for the study, employed the high-resolution adaptive optics system ALTAIR combined with the Gemini Near InfraRed Imager and spectrograph (NIRI). The researchers conducted a total of 271 observations between 2013 and 2018 and published their results in the July 2019 issue of The Astronomical Journal and the June 28, 2019 issue Geophysical Research Letters.

    While whizzing around Jupiter in an elliptical orbit with a period of only 1.8 days, Io’s interior is warmed by the varying pull of Jupiter’s gravity, roughly similar to how the Earth’s moon causes tides on our planet. This “tidal heating” powers Io’s volcanoes. However, the shape of Io’s orbit also changes, becoming alternately rounder and then more elliptical, over a longer period of about 480 days. The variation in Io’s orbital shape is caused by the more subtle effects of the varying gravitational pulls from Jupiter’s other large moons, mainly Europa and Ganymede.

    By studying changes in Io’s surface brightness due to its volcanic activity, researchers discovered a pattern in the volcanism that appears to coincide with the 480-day variation in the moon’s orbital shape. This was unexpected because there is no detectable pattern associated with the 1.8-day period of a single orbit, even though this is the amount of time over which the most dramatic variations in the pull of gravity occur. To understand this puzzling result, the researchers note that the magma is likely too viscous to react to the changing gravity on the timescale of one orbit, but it can adjust its flow rate with the slower variation in the shape of Io’s orbit. This explains the long-term variations in the degree of volcanic activity.

    Read more about this discovery and Io’s most powerful, persistent volcano, Loki Patera in this story from the American Geophysical Union.

    See the full article here .


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    Please help promote STEM in your local schools.


    Stem Education Coalition

    NOAO Gemini North on MaunaKea, Hawaii, USA, Altitude 4,213 m (13,822 ft)


    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet


    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 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.

     
  • richardmitnick 9:27 am on June 21, 2019 Permalink | Reply
    Tags: , , , , Gemini Observatory, GPI-Gemini Planet Imager South, It appears more and more likely that large planets and brown dwarfs have very different roots.   

    From Gemini Observatory: “The Formative Years: Giant Planets vs. Brown Dwarfs” 

    NOAO

    Gemini Observatory
    From Gemini Observatory

    June 12, 2019

    Science Contacts:

    Eric Nielsen
    Stanford University
    Email: enielsen”at”standard.edu
    Phone: (408) 394-4582

    Bruce Macintosh
    Stanford University
    Email: bmacint”at”standard.edu
    Phone: (650) 793-0969

    Franck Marchis
    SETI Institute
    Email: fmarchis”at”seti.org
    Phone: (510) 599-0604

    Media Contact:

    Peter Michaud
    Gemini Observatory, PIO Manager
    Email: pmichaud”at”gemini.edu
    Desk phone: 808-974-2510
    Cell phone: 808-936-6643

    Based on preliminary results from a new Gemini Observatory survey of 531 stars with the Gemini Planet Imager (GPI), it appears more and more likely that large planets and brown dwarfs have very different roots.

    The GPI Exoplanet Survey (GPIES), one of the largest and most sensitive direct imaging exoplanet surveys to date, is still ongoing at the Gemini South telescope [below] in Chile. “From our analysis of the first 300 stars observed, we are already seeing strong trends,” said Eric L. Nielsen of Stanford University, who is the lead author of the study, published in The Astronomical Journal.

    In November 2014, GPI Principal Investigator Bruce Macintosh of Stanford University and his international team set out to observe almost 600 young nearby stars with the newly commissioned instrument.

    NOAO Gemini Planet Imager on Gemini South

    GPI was funded with support from the Gemini Observatory partnership, with the largest portion from the US National Science Foundation (NSF). The NSF, and the Canadian National Research Council (NRC; also a Gemini partner), funded researchers participating in GPIES.

    Imaging a planet around another star is a difficult technical challenge possible with only a few instruments. Exoplanets are small, faint, and very close to their host star — distinguishing an orbiting planet from its star is like resolving the width of a dime from several miles away. Even the brightest planets are ten thousand times fainter than their parent star. GPI can see planets up to a million times fainter, much more sensitive than previous planet-imaging instruments. “GPI is a great tool for studying planets, and the Gemini Observatory gave us time to do a careful, systematic survey,” said Macintosh.

    GPIES is now coming to an end. From the first 300 stars, GPIES has detected six giant planets and three brown dwarfs. “This analysis of the first 300 stars observed by GPIES represents the largest, most sensitive direct imaging survey for giant planets published to date,” added Macintosh.

    Brown dwarfs are more massive than planets, but not massive enough to fuse hydrogen like stars. “Our analysis of this Gemini survey suggests that wide-separation giant planets may have formed differently from their brown dwarf cousins,” Nielsen said.

    The team’s paper advances the idea that massive planets form due to the slow accumulation of material surrounding a young star, while brown dwarfs come about due to rapid gravitational collapse. “It’s a bit like the difference between a gentle light rain and a thunderstorm,” said Macintosh.

    “With six detected planets and three detected brown dwarfs from our survey, along with unprecedented sensitivity to planets a few times the mass of Jupiter at orbital distances well beyond Jupiter’s, we can now answer some key questions, especially about where and how these objects form,” Nielsen said.

    This discovery may answer a longstanding question as to whether brown dwarfs — intermediate-mass objects — are born more like stars or planets. Stars form from the top down by the gravitational collapse of large primordial clouds of gas and dust, while planets are thought — but have not been confirmed — to form from the bottom up by the assembly of small rocky bodies that then grow into larger ones, a process also termed “core accretion.”

    “What the GPIES team’s analysis shows is that the properties of brown dwarfs and giant planets run completely counter to each other,” said Eugene Chiang, professor of astronomy at the University of California Berkeley and a co-author of the paper. “Whereas more massive brown dwarfs outnumber less massive brown dwarfs, for giant planets the trend is reversed: less massive planets outnumber more massive ones. Moreover, brown dwarfs tend to be found far from their host stars, while giant planets concentrate closer in. These opposing trends point to brown dwarfs forming top-down, and giant planets forming bottom-up.”

    More Surprises

    Of the 300 stars surveyed thus far, 123 are at least 1.5 times more massive than our Sun. One of the most striking results of the GPI survey is that all hosts of detected planets are among these higher-mass stars — even though it is easier to see a giant planet orbiting a fainter, more Sun-like star. Astronomers have suspected this relationship for years, but the GPIES survey has unambiguously confirmed it. This finding also supports the bottom-up formation scenario for planets.

    One of the study’s greatest surprises has been how different other planetary systems are from our own. Our Solar System has small rocky planets in the inner parts and giant gas planets in the outer parts. But the very first exoplanets discovered reversed this trend, with giant planets skimming closer to their stars than does moon-sized Mercury. Furthermore, radial-velocity studies — which rely on the fact that a star experiences a gravitationally induced “wobble” when it is orbited by a planet — have shown that the number of giant planets increases with distance from the star out to about Jupiter’s orbit.

    But the GPIES team’s preliminary results, which probe still larger distances, has shown that giant planets become less numerous farther out.

    “The region in the middle could be where you’re most likely to find planets larger than Jupiter around other stars,” added Nielsen, “which is very interesting since this is where we see Jupiter and Saturn in our own Solar System.” In this regard, the location of Jupiter in our own Solar System may fit the overall exoplanet trend.

    But a surprise from all exoplanet surveys is how intrinsically rare giant planets seem to be around Sun-like stars, and how different other solar systems are. The Kepler mission discovered far more small and close-in planets — two or more “super-Earth” planets per Sun-like star, densely packed into inner solar systems much more crowded than our own.

    NASA/Kepler Telescope, and K2 March 7, 2009 until November 15, 2018

    Extrapolation of simple models suggested GPI would find a dozen giant planets or more, but it only saw six. Putting it all together, giant planets may be present around only a minority of stars like our own.

    In January 2019, GPIES observed its 531st, and final, new star, and the team is currently following up the remaining candidates to determine which are truly planets and which are distant background stars impersonating giant planets.

    The next-generation telescopes — such as NASA’s James Webb Space Telescope and WFIRST mission, the Giant Magellan Telescope, Thirty Meter Telescope, and Extremely Large Telescope — should be able to push the boundaries of study, imaging planets much closer to their star and overlapping with other techniques, producing a full accounting of giant planet and brown dwarf populations from 1 to 1,000 AU.

    NASA/ESA/CSA Webb Telescope annotated

    NASA/WFIRST

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

    TMT-Thirty Meter Telescope, proposed and now approved for Mauna Kea, Hawaii, USA4,207 m (13,802 ft) above sea level

    ESO/E-ELT,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).

    “Further observations of additional higher mass stars can test whether this trend is real,” said Macintosh, “especially as our survey is limited by the number of bright, young nearby stars available for study by direct imagers like GPI.”

    See the full article here .


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


    Stem Education Coalition

    NOAO Gemini North on MaunaKea, Hawaii, USA, Altitude 4,213 m (13,822 ft)


    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet


    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 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.

     
  • richardmitnick 8:03 am on June 4, 2019 Permalink | Reply
    Tags: "Is the Mystery of the Dark Matter Deficient Galaxy Resolved?", , , , , , Gemini Observatory   

    From Gemini Observatory: “Is the Mystery of the Dark Matter Deficient Galaxy Resolved?” 

    NOAO

    Gemini Observatory
    From Gemini Observatory

    May 29, 2019

    To have, or not to have dark matter? That is the question.

    In early 2018, a team of researchers led by Pieter van Dokkum of Yale University shook up the astrophysics world when they announced that the dwarf, “ultra-diffuse galaxy,” which was referred to by van Dokkum as NGC 1052-DF2, is almost devoid of dark matter. Their report, published in the journal Nature, acknowledged that this conclusion depended on the distance to the galaxy. Nevertheless, the researchers presented evidence in favor of a distance that implied the galaxy was seriously light on dark matter.

    The problem is that the formation of galaxies without dark matter doesn’t fit most theories of galaxy evolution. If van Dokkum and his team are correct then astrophysicists have some serious explaining to do. The original Gemini summary of the van Dokkum et al. work can be found here. The van Dokkum team has also published a follow-up study in the September 1, 2018, issue of The Astrophysical Journal Letters which supports their original distance to the galaxy.

    2
    Color composite image of [KKS2000]04 combining F606W and F814W filters with black and white background using g-band very deep imaging from Gemini. The ultra-deep g-band Gemini data reveals a significant brightening of the galaxy in the northern region. An inset with a zoom into the inner region of the galaxy is shown. The zoom shows, with clarity, the presence of spatially resolved stars in the HST image.

    In the spirit of healthy scientific debate, another team, led by Ignacio Trujillo of the Instituto de Astrofísica de Canarias, used the same data as van Dokkum (including key Gemini Observatory imaging) and concluded that van Dokkum et al. overestimated the distance of the galaxy. Trujillo’s team argue that the galaxy is actually only a little more than half of what van Dokkum’s team determined (13 vs. 20 Megaparsecs). If this is correct, then, according to Trujillo, it resets the amount of dark matter to a level typical for a dwarf galaxy.

    It should be noted that Trujillo et al. use the original designation for the galaxy, KKS2000-04, because the distance they determined precludes an association with NGC 1052 as indicated by the van Dokkum designation.

    At the core of this debate are some of the assumptions made, and techniques used, to estimate the galaxy’s distance and determine its mass. Trujillo argues that his team’s reassessment of the data, which used multiple methods to arrive at the galaxy’s closer distance, provides a more solid foundation for estimating the galaxy’s distance. “The convergence of all five different and independent methods of measuring the distance to this galaxy reinforces the result,” said Trujillo.

    The new work by Trujillo et al. is published in the MNRAS and a press release issued by Instituto de Astrofísica de Canarias (IAC). A blog post discussion by Trujillo on measuring the distances to galaxies can be found here.

    See the full article here .


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    Please help promote STEM in your local schools.


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    NOAO Gemini North on MaunaKea, Hawaii, USA, Altitude 4,213 m (13,822 ft)


    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    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 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.

     
  • richardmitnick 9:18 am on March 22, 2019 Permalink | Reply
    Tags: , , , , , Gemini Observatory, , HP 1   

    From Gemini Observatory: “Ultra-sharp Images Make Old Stars Look Absolutely Marvelous! “ 

    NOAO

    Gemini Observatory
    From Gemini Observatory

    March 21, 2019

    Media Contact:

    Peter Michaud
    Public Information and Outreach manager
    Gemini Observatory
    Email: pmichaud”at”gemini.edu
    Desk: 808-974-2510
    Cell: 808-936-6643

    Science Contacts:

    Leandro Kerber
    Universidade Estadual de Santa Cruz, Brazil
    Email: lokerber”at”uesc.br
    Cell: +55 11 94724-6073
    Desk: +55 73 3680-5167

    1
    Figure 1. Color composite GSAOI+GeMS image of HP 1 obtained using the Gemini South telescope in Chile. North is up and East to the left. Composite image produced by Mattia Libralato of the Space Telescope Science Institute. Credit: Gemini Observatory/AURA/NSF.

    2
    GSAOI+GeMS color composite image of HP 1 (right image) shown relative to the full field of the cluster obtained by the Visible and Infrared Survey Telescope for Astronomy (left). Credit: Gemini Observatory/NSF/AURA/VISTA/Aladin/CDS.

    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.
    Credit: ESO/Y. Beletsky, with an elevation of 2,635 metres (8,645 ft) above sea level

    Using high-resolution adaptive optics imaging from the Gemini Observatory, astronomers have uncovered one of the oldest star clusters in the Milky Way Galaxy. The remarkably sharp image looks back into the early history of our Universe and sheds new insights on how our Galaxy formed.

    Just as high-definition imaging is transforming home entertainment, it is also advancing the way astronomers study the Universe.

    “Ultra-sharp adaptive optics images from the Gemini Observatory allowed us to determine the ages of some of the oldest stars in our Galaxy,” said Leandro Kerber of the Universidade de São Paulo and Universidade Estadual de Santa Cruz, Brazil. Kerber led a large international research team that published their results in the April 2019 issue of the Monthly Notices of the Royal Astronomical Society.

    Gemini Observatory Adaptie Optics-Gemini South on the summit of Cerro Pachón in Chile (left) and Gemini North on the summit of Mauna Kea in Hawai’i, USA (right). Image credit Gemini/NSF/AURA

    Using advanced adaptive optics technology at the Gemini South telescope in Chile, the researchers zoomed in on a cluster of stars known as HP 1. “Removing our atmosphere’s distortions to starlight with adaptive optics reveals tremendous details in the objects we study,” added Kerber. “Because we captured these stars in such great detail, we were able to determine their advanced age and piece together a very compelling story.”

    That story begins just as the Universe was reaching its one-billionth birthday.

    “This star cluster is like an ancient fossil buried deep in our Galaxy’s bulge, and now we’ve been able to date it to a far-off time when the Universe was very young,” said Stefano Souza, a PhD student at the Universidade de São Paulo, Brazil, who worked with Kerber as part of the research team. The team’s results date the cluster at about 12.8 billion years, making these stars among the oldest ever found in our Galaxy. “These are also some of the oldest stars we’ve seen anywhere,” added Souza.

    “HP 1 is one of the surviving members of the fundamental building blocks that assembled our Galaxy’s inner bulge,” said Kerber. Until a few years ago, astronomers believed that the oldest globular star clusters — spherical swarms of up to a million stars — were only located in the outer parts of the Milky Way, while the younger ones resided in the innermost Galactic regions. However, Kerber’s study, as well as other recent work based on data from the Gemini Observatory and the Hubble Space Telescope (HST), have revealed that ancient star clusters are also found within the Galactic bulge and relatively close to the Galactic center.

    Globular clusters tell us much about the formation and evolution of the Milky Way. Most of these ancient and massive stellar systems are thought to have coalesced out of the primordial gas cloud that later collapsed to form the spiral disk of our Galaxy, while others appear to be the cores of dwarf galaxies consumed by our Milky Way. Of the roughly 160 globular clusters known in our Galaxy, about a quarter are located within the greatly obscured and tightly packed central bulge region of the Milky Way. This spherical mass of stars some 10,000 light years across forms the central hub of the Milky Way (the yolk if you will) which is made primarily of old stars, gas, and dust. Among the clusters within the bulge, those that are the most metal-poor (lacking in heavier elements) – which includes HP 1 – have long been suspected of being the oldest. HP 1 then is pivotal, as it serves as an excellent tracer of our Galaxy’s early chemical evolution.

    “HP 1 is playing a critical role in our understanding of how the Milky Way formed,” Kerber said. “It is helping us to bridge the gap in our understanding between our Galaxy’s past and its present.”

    Kerber and his international team used the exquisitely deep high-resolution adaptive optics images from Gemini Observatory as well as archival optical images from the HST to identify faint cluster members, which are essential for age determination. With this rich data set they confirmed that HP 1 is a fossil relic born less than a billion years after the Big Bang, when the Universe was in its infancy.

    “These results crown an effort of more than two decades with some of the world’s premier telescopes aimed at determining accurate chemical abundances with high-resolution spectroscopy,” said Beatriz Barbuy of the Universidade de São Paulo, coauthor of this paper and a world-renowned expert in this field. “These Gemini images are the best ground-based photometric data we have. They are at the same level of HST data, allowing us to recover a missing piece in our puzzle: the age of HP 1. From the existence of such old objects, we can attest to the short star formation timescale in the Galactic bulge, as well as its fast chemical enrichment.”

    To determine the cluster’s distance, the team used archival ground-based data to identify 11 RR Lyrae variable stars (a type of “standard candle” used to measure cosmic distances) within HP 1. The observed brightness of these RR Lyrae stars indicate that HP 1 is at a distance of about 21,500 light years, placing it approximately 6,000 light years from the Galactic center, well within the Galaxy’s central bulge region.

    Kerber and his team also used the Gemini data, as well HST, Very Large Telescope, and Gaia mission data, to refine the orbit of HP 1 within our Galaxy. This analysis shows that during HP 1’s history, the cluster came as close as about 400 light years from the Galactic center – less than one-tenth of its current distance.

    NASA/ESA Hubble Telescope

    ESO VLT 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,

    ESA/GAIA satellite

    “The combination of high angular resolution and near-infrared sensitivity makes GeMS/GSAOI an extremely powerful tool for studying these compact, highly dust-enshrouded stellar clusters,” added Mattia Libralato of the Space Telescope Science Institute, a coauthor on the study. “Careful characterization of these ancient systems, as we’ve done here, is paramount to refine our knowledge of our Galaxy’s formation.”

    Chris Davis, Program Officer at the National Science Foundation (NSF) for Gemini, commented, “These fabulous results demonstrate why the development of wide-field, high-resolution imaging at Gemini is key to the Observatory’s future. The recent NSF award to support the development of a similar system at Gemini North will make routine super-sharp imaging from both hemispheres a reality. These are certainly exciting times for the Observatory.”

    The Gemini observations resolve stars to about 0.1 arcsecond which is one 36 thousandths of a degree and comparable to separating two automobile headlamps from approximately 1,500 miles, or 2,500 kilometers, away (the distance from Manaus to Sao Paulo in Brazil, or from San Francisco to Dallas in the USA). This resolution was obtained using the Gemini South Adaptive Optics Imager (GSAOI) – a near-infrared adaptive optics camera used with the Gemini Multi-conjugate adaptive optics System (GeMS). GeMS is an advanced adaptive optics system utilizing three deformable mirrors to correct for distortions imparted on starlight by turbulence in layers of our atmosphere.

    See the full article here .


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    Please help promote STEM in your local schools.


    Stem Education Coalition

    NOAO Gemini North on MaunaKea, Hawaii, USA, Altitude 4,213 m (13,822 ft)

    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    AURA Icon

    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 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.

     
  • richardmitnick 12:29 pm on February 7, 2019 Permalink | Reply
    Tags: , , , , “When we look at the information ALMA has provided we see about 60 different transitions – or unique fingerprints – of molecules like sodium chloride and potassium chloride coming from the disk", , , Gemini Observatory, Liberal Sprinkling of Salt Discovered around a Young Star, , Orion Source I, , The chemical fingerprints of sodium chloride (NaCl) and other similar salty compounds emanating from the dusty disk surrounding Orion Source I, The Orion Molecular Cloud 1   

    From ALMA: “Liberal Sprinkling of Salt Discovered around a Young Star” 

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    From ALMA

    7 February, 2019

    Valeria Foncea
    Education and Public Outreach Officer
    Joint ALMA Observatory Santiago – Chile
    Phone: +56 2 2467 6258
    Cell phone: +56 9 7587 1963
    Email: valeria.foncea@alma.cl

    Charles E. Blue
    Public Information Officer
    National Radio Astronomy Observatory Charlottesville, Virginia – USA
    Phone: +1 434 296 0314
    Cell phone: +1 202 236 6324
    Email: cblue@nrao.edu

    Calum Turner
    ESO Assistant Public Information Officer
    Garching bei München, Germany
    Phone: +49 89 3200 6670
    Email: calum.turner@eso.org

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

    1
    Artist impression of Orion Source I, a young, massive star about 1,500 light-years away. New ALMA observations detected a ring of salt — sodium chloride, ordinary table salt — surrounding the star. This is the first detection of salts of any kind associated with a young star. The blue region (about 1/3 the way out from the center of the disk) represents the region where ALMA detected the millimeter-wavelength “glow” from the salts. Credit: NRAO/AUI/NSF; S. Dagnello

    2
    ALMA image of the salty disk surrounding the young, massive star Orion Source I (blue ring). It is shown in relation to the Orion Molecular Cloud 1, a region of explosive starbirth. The background near infrared image was taken with the Gemini Observatory. Credit: ALMA (NRAO/ESO/NAOJ); NRAO/AUI/NSF; Gemini Observatory/AURA

    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    A team of astronomers and chemists using the Atacama Large Millimeter/submillimeter Array (ALMA) has detected the chemical fingerprints of sodium chloride (NaCl) and other similar salty compounds emanating from the dusty disk surrounding Orion Source I, a massive, young star in a dusty cloud behind the Orion Nebula.

    “It’s amazing we’re seeing these molecules at all,” said Adam Ginsburg, a Jansky Fellow of the National Radio Astronomy Observatory (NRAO) in Socorro, New Mexico, and lead author of a paper accepted for publication in The Astrophysical Journal. “Since we’ve only ever seen these compounds in the sloughed-off outer layers of dying stars, we don’t fully know what our new discovery means. The nature of the detection, however, shows that the environment around this star is very unusual.”

    To detect molecules in space, astronomers use radio telescopes to search for their chemical signatures – telltale spikes in the spread-out spectra of radio and millimeter-wavelength light. Atoms and molecules emit these signals in several ways, depending on the temperature of their environments.

    The new ALMA observations contain a bristling array of spectral signatures – or transitions, as astronomers refer to them – of the same molecules. To create such strong and varied molecular fingerprints, the temperature differences where the molecules reside must be extreme, ranging anywhere from 100 kelvin to 4,000 kelvin (about -175 Celsius to 3700 Celsius). An in-depth study of these spectral spikes could provide insights about how the star is heating the disk, which would also be a useful measure of the luminosity of the star.

    “When we look at the information ALMA has provided, we see about 60 different transitions – or unique fingerprints – of molecules like sodium chloride and potassium chloride coming from the disk. That is both shocking and exciting,” said Brett McGuire, a chemist at the NRAO in Charlottesville, Virginia, and co-author on the paper.

    The researchers speculate that these salts come from dust grains that collided and spilled their contents into the surrounding disk. Their observations confirm that the salty regions trace the location of the circumstellar disk.

    “Usually when we study protostars in this manner, the signals from the disk and the outflow from the star get muddled, making it difficult to distinguish one from the other,” said Ginsburg. “Since we can now isolate just the disk, we can learn how it is moving and how much mass it contains. It also may tell us new things about the star.”

    The detection of salts around a young star is also of interest to astronomers and astrochemists because some of constituent atoms of salts are metals – sodium and potassium. This suggests there may be other metal-containing molecules in this environment. If so, it may be possible to use similar observations to measure the amount of metals in star-forming regions. “This type of study is not available to us at all presently. Free-floating metallic compounds are generally invisible to radio astronomy,” noted McGuire.

    The salty signatures were found about 30 to 60 astronomical units (AU, or the average distance between the Earth and the Sun) from the host stars. Based on their observations, the astronomers infer that there may be as much as one sextillion (a one with 21 zeros after it) kilograms of salt in this region, which is roughly equivalent to the entire mass of Earth’s oceans.

    “Our next step in this research is to look for salts and metallic molecules in other regions. This will help us understand if these chemical fingerprints are a powerful tool to study a wide range of protoplanetary disks, or if this detection is unique to this source,” said Ginsburg. “In looking to the future, the planned Next Generation VLA would have the right mix of sensitivity and wavelength coverage to study these molecules and perhaps use them as tracers for planet-forming disks.”

    Orion Source I formed in the Orion Molecular Cloud I, a region of explosive starbirth previously observed with ALMA. “This star was ejected from its parent cloud with a speed of about 10 kilometers per second around 550 years ago,”1 said John Bally, an astronomer at the University of Colorado and co-author on the paper. “It is possible that solid grains of salt were vaporized by shock waves as the star and its disk were abruptly accelerated by a close encounter or collision with another star. It remains to be seen if salt vapor is present in all disks surrounding massive protostars, or if such vapor traces violent events like the one we observed with ALMA.”

    1. Light from this object took about 1,500 years to reach Earth. Astronomers are seeing it as if looking through that window of time, which reveals how it looked 550 years after it was ejected from its stellar nursery.

    See the full article here .

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    Please help promote STEM in your local schools.

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    The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA is funded in Europe by the European Organization for Astronomical Research in the Southern Hemisphere (ESO), in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and in East Asia by the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Academia Sinica (AS) in Taiwan.

    ALMA construction and operations are led on behalf of Europe by ESO, on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI) and on behalf of East Asia by the National Astronomical Observatory of Japan (NAOJ). The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

    NRAO Small
    ESO 50 Large
    NAOJ

     
    • iptv 1:43 am on February 13, 2019 Permalink | Reply

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  • richardmitnick 10:32 am on January 11, 2019 Permalink | Reply
    Tags: , , , Cosmic Telescope Zooms in on the Beginning of Time, , Gemini Observatory, Quasar known as J0439+1634,   

    From Gemini Observatory: “Cosmic Telescope Zooms in on the Beginning of Time” 

    NOAO

    Gemini Observatory
    From Gemini Observatory

    January 9, 2019

    Media Contact:

    Peter Michaud
    Public Information and Outreach manager
    Gemini Observatory
    Email: pmichaud@gemini.edu
    Desk: 808-974-2510
    Cell: 808-936-6643

    Science Contacts:

    Xiaohui Fan
    Regents’ Professor of Astronomy
    Steward Observatory
    University of Arizona
    Email: fan@as.arizona.edu
    Desk: 520-360-0956

    John Blakeslee
    Head Scientist
    Gemini Observatory, La Serena, Chile
    Email: jblakeslee@gemini.edu
    Desk: 56-51-2205-628

    The scientific result described in this release is based on a presentation at the 233rd meeting of the American Astronomical Society in Seattle, Washington and published in The Astrophysical Journal Letters. The research was sponsored by grants from the U.S. National Science Foundation (NSF) Division of Astronomical Sciences and NASA. The National Science Foundation also supports the Gemini Observatory.

    Observations from Gemini Observatory identify a key fingerprint of an extremely distant quasar, allowing astronomers to sample light emitted from the dawn of time. Astronomers happened upon this deep glimpse into space and time thanks to an unremarkable foreground galaxy acting as a gravitational lens, which magnified the quasar’s ancient light.

    Gravitational Lensing NASA/ESA

    The Gemini observations provide critical pieces of the puzzle in confirming this object as the brightest appearing quasar so early in the history of the Universe, raising hopes that more sources like this will be found.

    1
    A number of large telescopes were used to observe quasar J0439+1634 in the optical and infrared light. The 6.5m MMT Telescope was used to discovery this distant quasar.

    CfA U Arizona Fred Lawrence Whipple Observatory Steward Observatory MMT Telescope at the summit of Mount Hopkins near Tucson, Arizona, USA, Altitude 2,616 m (8,583 ft)

    It and the 10m Keck-I Telescope obtained a sensitive spectrum of the quasar in optical light.

    Keck 1 Telescope, Keck Observatory, Maunakea, Hawaii, USA.4,207 m (13,802 ft), above sea level,

    The 8.1m Gemini Telescope obtained an infrared spectrum that accurately determined the quasar distance and the mass of its powerful black hole.

    The 2×8.4m Large Binocular Telescope captured an adaptive optics corrected image that suggests the quasar is lensed, later confirmed by the sharper Hubble image. Credit: Feige Wang (UCSB), Xiaohui Fan (University of Arizona)

    U Arizona Large Binocular Telescope, 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. Image credit: NASA/JPL-Caltech.

    Before the cosmos reached its billionth birthday, some of the very first cosmic light began a long journey through the expanding Universe. One particular beam of light, from an energetic source called a quasar, serendipitously passed near an intervening galaxy, whose gravity bent and magnified the quasar’s light and refocused it in our direction, allowing telescopes like Gemini North to probe the quasar in great detail.

    “If it weren’t for this makeshift cosmic telescope, the quasar’s light would appear about 50 times dimmer,” said Xiaohui Fan of the University of Arizona who led the study. “This discovery demonstrates that strongly gravitationally lensed quasars do exist despite the fact that we’ve been looking for over 20 years and not found any others this far back in time.”

    The Gemini observations provided key pieces of the puzzle by filling a critical hole in the data. The Gemini North telescope on Maunakea, Hawai‘i, utilized the Gemini Near-InfraRed Spectrograph (GNIRS) to dissect a significant swath of the infrared part of the light’s spectrum.


    Gemini/North telescope at Maunakea, Hawaii, USA,4,207 m (13,802 ft) above sea level


    Gemini Near-Infrared Spectrograph on Gemini North, Mauna Kea, Hawaii USA

    The Gemini data contained the tell-tale signature of magnesium which is critical for determining how far back in time we are looking. The Gemini observations also led to a determination of the mass of the black hole powering the quasar. “When we combined the Gemini data with observations from multiple observatories on Maunakea, the Hubble Space Telescope, and other observatories around the world, we were able to paint a complete picture of the quasar and the intervening galaxy,” said Feige Wang of the University of California, Santa Barbara, who is a member of the discovery team.

    That picture reveals that the quasar is located extremely far back in time and space – shortly after what is known as the Epoch of Reionization — when the very first light emerged from the Big Bang.

    Reionization era and first stars, Caltech

    “This is one of the first sources to shine as the Universe emerged from the cosmic dark ages,” said Jinyi Yang of the University of Arizona, another member of the discovery team. “Prior to this, no stars, quasars, or galaxies had been formed, until objects like this appeared like candles in the dark.”

    The foreground galaxy that enhances our view of the quasar is especially dim, which is extremely fortuitous. “If this galaxy were much brighter, we wouldn’t have been able to differentiate it from the quasar,” explained Fan, adding that this finding will change the way astronomers look for lensed quasars in the future and could significantly increase the number of lensed quasar discoveries. However, as Fan suggested, “We don’t expect to find many quasars brighter than this one in the whole observable Universe.”

    The intense brilliance of the quasar, known as J0439+1634 (J0439+1634 for short), also suggests that it is fueled by a supermassive black hole at the heart of a young forming galaxy. The broad appearance of the magnesium fingerprint captured by Gemini also allowed astronomers to measure the mass of the quasar’s supermassive black hole at 700 million times that of the Sun. The supermassive black hole is most likely surrounded by a sizable flattened disk of dust and gas. This torus of matter — known as an accretion disk — most likely continually spirals inward to feed the black hole powerhouse. Observations at submillimeter wavelengths with the James Clerk Maxwell Telescope on Maunakea suggest that the black hole is not only accreting gas but may be triggering star birth at a prodigious rate — which appears to be up to 10,000 stars per year; by comparison, our Milky Way Galaxy makes one star per year. However, because of the boosting effect of gravitational lensing, the actual rate of star formation could be much lower.

    Quasars are extremely energetic sources powered by huge black holes thought to have resided in the very first galaxies to form in the Universe. Because of their brightness and distance, quasars provide a unique glimpse into the conditions in the early Universe. This quasar has a redshift of 6.51, which translates to a distance of 12.8 billion light years, and appears to shine with a combined light of about 600 trillion Suns, boosted by the gravitational lensing magnification. The foreground galaxy which bent the quasar’s light is about half that distance away, at a mere 6 billion light years from us.

    Fan’s team selected J0439+1634 as a very distant quasar candidate based on optical data from several sources: the Panoramic Survey Telescope and Rapid Response System1 (Pan-STARRS1; operated by the University of Hawai‘i’s Institute for Astronomy), the United Kingdom Infra-Red Telescope Hemisphere Survey (conducted on Maunakea, Hawai‘i), and NASA’s Wide-field Infrared Survey Explorer (WISE) space telescope archive.

    Pann-STARSR1 Telescope, U Hawaii, Mauna Kea, Hawaii, USA, Altitude 3,052 m (10,013 ft)


    UKIRT, located on Mauna Kea, Hawai’i, USA as part of Mauna Kea Observatory,4,207 m (13,802 ft) above sea level

    NASA Wise Telescope

    The first follow-up spectroscopic observations, conducted at the Multi-Mirror Telescope in Arizona, confirmed the object as a high-redshift quasar. Subsequent observations with the Gemini North and Keck I telescopes in Hawai‘i confirmed the MMT’s finding, and led to Gemini’s detection of the crucial magnesium fingerprint — the key to nailing down the quasar’s fantastic distance. However, the foreground lensing galaxy and the quasar appear so close that it is impossible to separate them with images taken from the ground due to blurring of the Earth’s atmosphere. It took the exquisitely sharp images by the Hubble Space Telescope to reveal that the quasar image is split into three components by a faint lensing galaxy.r.

    The quasar is ripe for future scrutiny. Astronomers also plan to use the Atacama Large Millimeter/submillimeter Array, and eventually NASA’s James Webb Space Telescope, to look within 150 light-years of the black hole and directly detect the influence of the gravity from black hole on gas motion and star formation in its vicinity.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    NASA/ESA/CSA Webb Telescope annotated

    Any future discoveries of very distant quasars like J0439+1634 will continue to teach astronomers about the chemical environment and the growth of massive black holes in our early Universe.

    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/North telescope at Maunakea, Hawaii, USA,4,207 m (13,802 ft) above sea level

    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    AURA Icon

    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 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.

     
  • richardmitnick 3:22 pm on November 5, 2018 Permalink | Reply
    Tags: , , , , , Gemini Observatory, Tiny Old Star Has Huge Impact   

    From Gemini Observatory: “Tiny Old Star Has Huge Impact” 

    NOAO

    Gemini Observatory
    From Gemini Observatory

    November 5th, 2018

    Media Contacts:

    Peter Michaud
    Public Information and Outreach manager
    Gemini Observatory
    Email: pmichaud”at”gemini.edu
    Phone: 808-974-2510
    Cell: 808-936-6643

    Jill Rosen
    Senior Media Relations Representative
    Johns Hopkins University
    Email: jrosen”at”jhu.edu
    Desk: 443-997-9906
    Cell: 443-547-8805

    Science Contact:

    Kevin Schlaufman
    Assistant Professor of Physics and Astronomy
    Johns Hopkins University
    Email: kschlaufman”at”jhu.edu
    Office Phone: 410-516-3295
    Cell Phone: 814-490-9177

    1
    The new discovery is only 14% the size of the Sun and is the new record holder for the star with the smallest complement of heavy elements. It has about the same heavy element proportion as Mercury, the smallest planet in our solar system. Credit: Kevin Schlaufman.

    Astronomers use the Gemini Observatory to investigate a tiny star that is likely the oldest known star in the disk of our galaxy. The diminutive star could have a disproportionate impact on our understanding of the age and history of our Milky Way Galaxy. It also provides a unique glimpse into the conditions present in the young Universe shortly after the Big Bang.

    A tiny star found in our galactic neighborhood is presenting astronomers with a compelling glimpse into the history of our galaxy and the early Universe. The star has some very interesting characteristics: it’s small, it’s old, and most significantly it’s made of material very similar to that spewed by the Big Bang. To host a star like this suggests that the disk of our galaxy could be up to three billion years older than previously thought.

    “Our Sun likely descended from thousands of generations of short-lived massive stars that have lived and died since the Big Bang,” said Kevin Schlaufman of Johns Hopkins University, leader of this study published in the November 5th issue of The Astrophysical Journal. “However, what’s most interesting about this star is that it had perhaps only one ancestor separating it and the beginnings of everything,” Schlaufman adds.

    The Big Bang theory dates our Universe at about 13.7 billion years and suggests that the first stars were made almost exclusively of hydrogen and helium. As stars die and gradually recycle their materials into new stars, heavier elements formed. Astronomers refer to stars which lack heavier elements as low metallicity stars. “But this one has such low metallicity,” said Schlaufman, “it’s known as an ultra metal poor star – this star may be one in ten million.”

    The star, which goes by the designation 2MASS J18082002-5104378 B, also challenges the assumption that the first stars in the Universe were large, exclusively high-mass and short-lived stars. In addition, its location within the usually active and crowded disk of our galaxy is unexpected.

    2MASS J18082002–5104378 B is a part of a binary star system. It is the smaller companion to a larger low-metallicity star observed in 2014 and 2015 by the European Southern Observatory’s Very Large Telescope UT2.

    ESO VLT 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

    Before the discovery of the tiny star, astronomers mistakenly believed that this binary system might contain a black hole or neutron star. From April 2016 to July 2017, Schlaufman and his team used both the Gemini Multi-Object Spectrograph (GMOS) on the Gemini South telescope in Chile and the Magellan Clay Telescope at Las Campanas Observatory to dissect the star system’s light and measure the object’s relative motions, thus discovering the tiny star by detecting its gravitational tug on its partner.

    Las Campanas Clay Magellan telescope, located at Carnegie’s Las Campanas Observatory, Chile, approximately 100 kilometres (62 mi) northeast of the city of La Serena, over 2,500 m (8,200 ft) high

    Gemini Observatory GMOS on Gemini South

    “Gemini was critical to this discovery, as its flexible observing modes enabled weekly check-ins on the system over six months,” Schlaufman confirms.

    “Understanding the history of our own galaxy is critical for humanity to understand the broader history of the entire Universe,” said Chris Davis of the United State’s National Science Foundation (NSF). NSF funds the Gemini Observatory on behalf of the United States, additional international partners are listed at the end of this release.

    2MASS J18082002–5104378 B has only about 14% the mass of our Sun making it a red dwarf star. While average-sized stars like our Sun live for approximately 10 billion years before extinguishing their nuclear fuel, low-mass stars can burn for trillions of years.

    “Diminutive stars like these tend to shine for a very long time,” said Schlaufman. “This star has aged well. It looks exactly the same today as it did when it formed 13.5 billion years ago.”

    The discovery of 2MASS J18082002–5104378 B gives astronomers hope for finding more of these old stars which provide a glimpse at the very early Universe. Only about 30 ultra metal poor stars have been identified. “Observations such as these are paving the way to perhaps one day finding that ever elusive first generation star,” concludes Schlaufman.

    See the full article here.
    See also the Monash University article here .


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


    Stem Education Coalition

    Gemini/North telescope at Maunakea, Hawaii, USA,4,207 m (13,802 ft) above sea level

    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    AURA Icon

    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 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.

     
  • richardmitnick 9:29 pm on October 17, 2018 Permalink | Reply
    Tags: , , , , Gemini Near-Infrared Spectrograph on Gemini North, , Gemini Observatory, Hawaii USA, , Sierra Remote Observatory, The core-collapse supernova 2017eaw   

    From Gemini Observatory: “Nearby Supernova Sheds Light on Ancient Dust” 

    NOAO

    Gemini Observatory
    From Gemini Observatory

    October 16, 2018

    Thanks to two allocations of Director’s Discretionary Time and a successful Fast-Turnaround program, an international team (including Gemini Emeritus Astronomer Tom Geballe, who wrote this summary on behalf of the team) used Gemini North/GNIRS to follow the evolution of the near-infrared spectrum of the core-collapse supernova 2017eaw (ccSN 2017eaw) over three semesters.

    Gemini Near-Infrared Spectrograph on Gemini North, Mauna Kea, Hawaii USA

    The data obtained from this relatively nearby event may help us to better understand the existence of dusty galaxies in the early, much more distant Universe.

    One of the unexpected discoveries in studies of the very early Universe is that many high redshift galaxies are “dusty.” These dusty galaxies exist as recently as several hundred million to a billion years after the Big Bang. The origin of this dust is somewhat of a mystery, because stars with masses similar to the Sun, which constitute the vast majority of stars in a galaxy, would not have evolved to the dust-producing stage in such a short time. Thus, there must be another source of dust in these very distant and very young galaxies.

    __________________________________________________
    Where Does Interstellar Dust Originate?

    Interstellar dust constitutes about 1% of the mass of interstellar matter in our Milky Way and in many other galaxies. It is generally understood that the origin of most of that dust is stars with masses roughly similar to that of our Sun, that became red giants and ejected their outer layers into space. Although initially almost entirely hydrogen and helium, during the red giant phase the outer layers of those stars are polluted by heavier elements such as carbon, nitrogen, oxygen, silicon, magnesium, and many others that are produced by thermonuclear reactions deep inside the stars and then mixed into the outer layers. Once the ejecta cool to temperatures lower than about 2,000 K, dust particles inevitably start to form out of these heavy elements. However, it is billions of years after these stars formed when this happens. On the other hand, core collapse supernovae live only a few millions to a few tens of millions of years before they explode, during which time they turn most of their hydrogen-rich and helium-rich interiors into vast reservoirs of heavy elements. Thus, unlike stars like the Sun, massive stars are potential dust-producers in the early Universe.
    __________________________________________________

    One possible source is the ejecta from massive stars that explode after only a few millions to a few tens of millions of years after they form, the so-called core-collapse supernovae (ccSNe).

    1
    Figure 1. Image of spiral galaxy NGC 6946 and SN 2017eaw indicated by arrow. Photo courtesy of Damian Peach, obtained on May 28th, 2017, at 10:31 UTC from the Sierra Remote Observatory, California.

    Sierra Remote Observatory in the Sierra Nevada Mountains, a mountain range in the Western United States, between the Central Valley of California and the Great Basin

    2
    The Great Basin is the largest area of contiguous endorheic watersheds in North America. It spans nearly all of Nevada, much of Oregon and Utah, and portions of California, Idaho, and Wyoming.

    While we cannot study individual supernovae in such distant galaxies, we can find examples of them in the nearby Universe. Infrared- and millimeter-wave observations of several “local” examples have revealed that ccSNe can produce copious amounts of dust — up to one solar mass for each event. Until now, however, detailed evolution of dust production in such supernovae, which can take place over several years, has only been followed in one object: the very nearby, famous, and rather unusual ccSN 1987A in the Large Magellanic Cloud. Fortuitously, our recent observations of ccSN 2017eaw in the nearby galaxy NGC 6946 provided another rare opportunity to follow that evolution in detail over an extended period. NGC 6946 is located about 7 megaparsecs away and is popularly known as the Fireworks Galaxy, because it is a prodigious supplier of supernovae (see Figure 1 and a pre-SN 2017eaw Gemini Legacy Image of NGC 6946).

    SN 2017eaw was discovered on May 14, 2017, just as its host galaxy, NGC 6946, became observable in the eastern sky before dawn. Because of its high northerly location, we saw an opportunity to follow SN 2017eaw continuously from May until December (before it became too low in the western sky to observe from Maunakea) and proposed the idea to Gemini Observatory. Thanks to two allocations of Director’s Discretionary Time and a successful Fast-Turnaround program, the team led by Jeonghee Rho (SETI Institute) was able to follow the evolution of the supernova’s near-infrared (0.84-2.52 micron) spectrum in Semesters 2017A, 2017B, and 2018A. The team also includes Tom Geballe (Gemini Observatory), Dipankar Banerjee and Vishal Joshi (Physical Research Laboratory, Ahmedabad, India), Nye Evans (Keele University, U.K.), and Luc Dessart (Universidad de Chile).

    During 2017-18, we obtained Gemini North/GNIRS (Gemini Near-InfraRed Spectrometer) data on ten dates between 22 and 387 days after the discovery. It is believed that these data represent the highest quality and most extensive near-infrared time-sequence of spectra ever obtained for a Type II-P SN, the most common type of ccSN, whose light curve has a distinctive flat stretch (called a plateau).

    The first nine of these spectra, obtained in 2017, are shown in Figure 2. While they are a goldmine of information — revealing details on elemental abundances, nucleosynthesis, changes in ionization, and velocities of the ejecta — our major goal was to witness and model the formation of the molecule carbon monoxide (CO) and dust, which is quite hot when it forms. Information on these species is contained only at the long wavelength end of the spectra, from 2.0 to 2.5 microns.

    CO is important because it is a powerful coolant of the ejecta, which aids in making dust formation possible. Its presence is clearly detected on day 124 by the sharp increase in signal near 2.30 microns, and we think it was already marginally present at day 107. The dust signature also begins at day 124, and is the flattening slope of the continuum from 2.1 microns to longer wavelengths, compared to the steadily decreasing continuum signal at shorter wavelengths, and across the entire spectrum at earlier times.

    We have used the spectra to estimate the CO mass produced by SN 2017eaw and find that it is qualitatively matched by models in the literature of a progenitor star of mass roughly 15 times that of the Sun. Fits to the continuum indicate that the temperature of the dust emitting at 2.1-2.5 microns is ~ 1,300 K and that the dust is mainly graphitic, which, unlike amorphous carbon, can condense at higher temperatures than this. Discussion of these and other results and analysis are reported in Rho et al., The Astrophysical Journal Letters, 864: L20, 2018.

    We are continuing our monitoring of SN 2017eaw in Semester 2018B; thereafter it will be too faint. In future semesters, we hope to measure additional nearby ccSNe that occur in order to estimate the frequency of CO and dust production by such SNe, as well as the masses of CO and dust produced by each.

    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/North telescope at Maunakea, Hawaii, USA,4,207 m (13,802 ft) above sea level

    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    AURA Icon

    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 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.

     
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