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  • richardmitnick 11:30 am on May 24, 2017 Permalink | Reply
    Tags: , , , , Inflating Sh2-308, NASA ESA Hubble   

    From Hubble: “Inflating Sh2-308” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope

    NASA/ESA Hubble Telescope

    Undated
    No writer credit

    1

    The NASA/ESA Hubble Space Telescope still has a few tricks up its sleeve in its task of exploring the Universe. For one, it is able to image two adjacent parts of the sky simultaneously. It does this using two different cameras — one camera can be trained on the target object itself, and the other on a nearby patch of sky so that new and potentially interesting regions of the cosmos can be observed at the same time (these latter observations are known as parallel fields).

    This image shows part of a bubble-like cloud of gas — a nebula named Sh2-308 — surrounding a massive and violent star named EZ Canis Majoris. It uses observations from Hubble’s Advanced Camera for Surveys, and is the parallel field associated with another view of the nebula produced by Hubble’s Wide Field Camera 3.

    NASA/ESA Hubble ACS

    NASA/ESA Hubble WFC3

    EZ Canis Majoris is something known as a Wolf-Rayet star, and is one of the brightest known stars of its kind. Its outer shell of hydrogen gas has been used up, revealing inner layers of heavier elements that burn at ferocious temperatures. The intense radiation pouring out from EZ Canis Majoris forms thick stellar winds that whip up nearby material, sculpting and blowing it outwards.

    These processes have moulded the surrounding gas into a vast bubble. A bubble nebula produced by a Wolf-Rayet star is made of ionised hydrogen (HII), which is often found in interstellar space. In this case, it is the outer hydrogen layers of EZ Canis Majoris — the bubble — that are being inflated by the deluge of radiation — the air — coming from the central star. The fringes of these bubbles are nebulous and wispy, as can be seen in this image.

    Credit:

    NASA/ESA Hubble

    See the full article here .

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    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 9:01 am on May 23, 2017 Permalink | Reply
    Tags: , , , , Elliptical galaxy NGC 3610, , NASA ESA Hubble   

    From Manu: “The evolution of elliptical galaxies, NGC 3610” 


    Manu Garcia, a friend from IAC.

    Manu needs a new happier picture.

    The universe around us.
    Astronomy, everything you wanted to know about our local universe and never dared to ask.

    1

    In the center of this amazing image is the elliptical galaxy NGC 3610. around the galaxy there is a lot of other galaxies of all forms, we can find spiral galaxies, galaxies with a bar in their central regions, galaxies, elliptical galaxies and distorted All visible in the background. In fact, almost every bright spot in this picture is a galaxy, the few stars in the foreground are clearly distinguishable because diffraction spikes that overlap their images.

    NGC 3610 is the most outstanding object in this picture and very interesting for it. Discovered in 1793 by William Herschel is situated at a distance of 80 million light-years away in the constellation of ursa major, it was later discovered that this elliptical galaxy contains a record. This is very unusual, because the albums are one of the main hallmarks of a spiral galaxy and of NGC 3610 it even has a shiny disc.

    The reason of the peculiar form of NGC 3610 derives from its history of formation. When galaxies form, usually resemble our galaxy, the milky way, with flat discs and spiral arms where the star formation rates are high and therefore are very brilliant. An elliptical galaxy is an object much more messy resulting from the merger of two or more galaxies. During these violent mergers is destroyed most of the internal structure of the original star wars. The fact that NGC 3610 still shows some structure in the form of a shiny disc implies that formed recently. The age of the galaxy has been put into about four billion years and is an important object for the study of the early stages of the evolution in elliptical galaxies.

    Credit:
    Esa / Hubble & NASA, recognition: Judy Schmidt.

    Visit My blog:
    http://eluniversodemanu.blogspot.com

    See the full article here .

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  • richardmitnick 6:53 am on May 23, 2017 Permalink | Reply
    Tags: a massive and violent star called EZ Canis Majoris, , , , , , NASA ESA Hubble, Sh2-308   

    From Manu Garcia: ” Sh2-308, a bubble” 


    Manu Garcia, a friend from IAC.

    Manu needs a happier picture. He is really a nice guy.

    The universe around us.
    Astronomy, everything you wanted to know about our local universe and never dared to ask.

    23/5/17
    Cosmic blowing bubbles

    1
    The NASA/ESA Hubble Space Telescope still has some tricks up his sleeve in his task of exploring the universe. On the one hand, it is able to imagine two adjacent parts of the sky simultaneously. This is done with two different cameras, a camera can be trained on the target object itself, and the other in a patch of nearby sky for new and potentially interesting regions of the cosmos can be observed simultaneously (the latter observations are known as parallel fields).

    NASA/ESA Hubble Telescope

    NASA/ESA Hubble ACS

    NASA/ESA Hubble WFC3

    This fascinating image shows some of the slender threads that make Sh2-308 , a thin, weak layer of gas located at 5,200 light – years away in the constellation Canis Major, Canis Major. This image shows part of a bubble like a cloud of gas, Sh2-308, surrounding a massive, violent star called EZ Canis Majoris . Advanced camera observations Hubble drilling are used and for the associated field parallel another view of the nebula produced by the wide field camera 3 Hubble used.

    EZ Canis Majoris is known as a Wolf-Rayet star, and is one of the brightest stars known of its kind. Wolf-Rayet type stars are among the brightest and most massive massive stars in the universe, dozens of times our own sun represent the extremes of stellar evolution. Continuous heavy winds spilling the progenitors of such stars flooding and draining around the outer layers of the Wolf-Rayet stars. The rapid wind of a Wolf-Rayet star, therefore, sweeps the surrounding material to form gas bubbles. Its outer layer of hydrogen gas is exhausted, revealing inner layers of heavier elements fierce burning temperatures. The intense radiation leaving EZ Canis Majoris forms large stellar winds fluttering nearby material, sculpting and blowing outward.

    These processes have shaped the surrounding gas in a large bubble. A hazy bubble produced by a Wolf-Rayet star is formed of ionized hydrogen (HII), which is often found in interstellar space. In this case, the outer layers are hydrogen EZ Canis Majoris, bubble, those being inflated by the flood of radiation, the air from the central star. The fringes of these bubbles are dark and spacious as you can see in this picture.

    EZ Canis Majoris is responsible for creating the bubble Sh2-308 , the star threw off its outer layers to create the visible strands here. The intense and continuous radiation from the star bubble pushes farther and farther away, making getting bigger. Currently the edges of Sh2-308 are about 60 light years away. Beautiful as are these cosmic bubbles are fleeting. The same stars that form will also cause his death, eclipsándolas and sumiéndolas in a violent supernova explosion.

    Credit:
    ESA / Hubble and NASA

    See the full article here .
    See the ESA/Hubble article here . I prefer Manu because he is a friend of mine, a good friend in Astronomy.

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  • richardmitnick 1:01 pm on May 18, 2017 Permalink | Reply
    Tags: , , , , Moon Around the Dwarf Planet 2007 OR10, NASA ESA Hubble   

    From Hubble: “Hubble Spots Moon Around Third Largest Dwarf Planet” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope

    NASA/ESA Hubble Telescope

    Donna Weaver
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4493 /
    dweaver@stsci.edu /

    Ray Villard
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4514
    villard@stsci.edu

    Csaba Kiss
    Konkoly Observatory, Budapest, Hungary
    011-36-1-391-9341
    kiss.csaba@csfk.mta.hu

    John Stansberry
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-2442
    jstans@stsci.edu

    1
    Moon Around the Dwarf Planet 2007 OR10

    The combined power of three space observatories, including NASA’s Hubble Space Telescope, has helped astronomers uncover a moon orbiting the third largest dwarf planet, catalogued as 2007 OR10. The pair resides in the frigid outskirts of our solar system called the Kuiper Belt, a realm of icy debris left over from our solar system’s formation 4.6 billion years ago.

    With this discovery, most of the known dwarf planets in the Kuiper Belt larger than 600 miles across have companions. These bodies provide insight into how moons formed in the young solar system.

    Kuiper Belt. Minor Planet Center

    “The discovery of satellites around all of the known large dwarf planets — except for Sedna — means that at the time these bodies formed billions of years ago, collisions must have been more frequent, and that’s a constraint on the formation models,” said Csaba Kiss of the Konkoly Observatory in Budapest, Hungary. He is the lead author of the science paper announcing the moon’s discovery. “If there were frequent collisions, then it was quite easy to form these satellites.”

    The objects most likely slammed into each other more often because they inhabited a crowded region. “There must have been a fairly high density of objects, and some of them were massive bodies that were perturbing the orbits of smaller bodies,” said team member John Stansberry of the Space Telescope Science Institute in Baltimore, Maryland. “This gravitational stirring may have nudged the bodies out of their orbits and increased their relative velocities, which may have resulted in collisions.”

    But the speed of the colliding objects could not have been too fast or too slow, according to the astronomers. If the impact velocity was too fast, the smash-up would have created lots of debris that could have escaped from the system; too slow and the collision would have produced only an impact crater.

    Collisions in the asteroid belt, for example, are destructive because objects are traveling fast when they smash together. The asteroid belt is a region of rocky debris between the orbits of Mars and the gas giant Jupiter. Jupiter’s powerful gravity speeds up the orbits of asteroids, generating violent impacts.

    The team uncovered the moon in archival images of 2007 OR10 taken by Hubble’s Wide Field Camera 3. Observations taken of the dwarf planet by NASA’s Kepler Space Telescope first tipped off the astronomers of the possibility of a moon circling it.

    NASA/Kepler Telescope

    Kepler revealed that 2007 OR10 has a slow rotation period of 45 hours. “Typical rotation periods for Kuiper Belt Objects are under 24 hours,” Kiss said. “We looked in the Hubble archive because the slower rotation period could have been caused by the gravitational tug of a moon. The initial investigator missed the moon in the Hubble images because it is very faint.”

    The astronomers spotted the moon in two separate Hubble observations spaced a year apart. The images show that the moon is gravitationally bound to 2007 OR10 because it moves with the dwarf planet, as seen against a background of stars. However, the two observations did not provide enough information for the astronomers to determine an orbit.

    “Ironically, because we don’t know the orbit, the link between the satellite and the slow rotation rate is unclear,” Stansberry said.

    The astronomers calculated the diameters of both objects based on observations in far-infrared light by the Herschel Space Observatory, which measured the thermal emission of the distant worlds. The dwarf planet is about 950 miles across, and the moon is estimated to be 150 miles to 250 miles in diameter. 2007 OR10, like Pluto, follows an eccentric orbit, but it is currently three times farther than Pluto is from the sun.

    ESA/Herschel spacecraft

    2007 OR10 is a member of an exclusive club of nine dwarf planets. Of those bodies, only Pluto and Eris are larger than 2007 OR10. It was discovered in 2007 by astronomers Meg Schwamb, Mike Brown, and David Rabinowitz as part of a survey to search for distant solar system bodies using the Samuel Oschin Telescope at the Palomar Observatory in California.

    Caltech Palomar Samuel Oschin 48 inch Telescope Interior with Edwin Hubble

    Caltech Palomar Samuel Oschin 48 inch Telescope

    The team’s results appeared in The Astrophysical Journal Letters.

    Credits

    NASA, ESA, C. Kiss (Konkoly Observatory), and J. Stansberry (STScI)

    See the full article here .

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    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 12:20 pm on May 4, 2017 Permalink | Reply
    Tags: , , , , , NASA ESA Hubble   

    From Hubble: “The final frontier of the Frontier Fields” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope

    NASA/ESA Hubble Telescope

    4 May 2017
    Mathias Jäger
    ESA/Hubble, Public Information Officer
    Garching bei München, Germany
    Tel: +49 176 6239750
    mjaeger@partner.eso.org

    1
    The NASA/ESA Hubble Telescope has peered across six billion light years of space to resolve extremely faint features of the galaxy cluster Abell 370 that have not been seen before. Imaged here in stunning detail, Abell 370 is part of the Frontier Fields programme which uses massive galaxy clusters to study the mysteries of dark matter and the very early Universe.

    Six billion light-years away in the constellation Cetus (the Sea Monster), Abell 370 is made up of hundreds of galaxies [1]. Already in the mid-1980s higher-resolution images of the cluster showed that the giant luminous arc in the lower left of the image was not a curious structure within the cluster, but rather an astrophysical phenomenon: the gravitationally lensed image of a galaxy twice as far away as the cluster itself. Hubble helped show that this arc is composed of two distorted images of an ordinary spiral galaxy that just happens to lie behind the cluster.

    Abell 370’s enormous gravitational influence warps the shape of spacetime around it, causing the light of background galaxies to spread out along multiple paths and appear both distorted and magnified. The effect can be seen as a series of streaks and arcs curving around the centre of the image. Massive galaxy clusters can therefore act like natural telescopes, giving astronomers a close-up view of the very distant galaxies behind the cluster — a glimpse of the Universe in its infancy, only a few hundred million years after the Big Bang.

    This image of Abell 370 was captured as part of the Frontier Fields programme, which used a whopping 630 hours of Hubble observing time, over 560 orbits of the Earth. Six clusters of galaxies were imaged in exquisite detail, including Abell 370 which was the very last one to be finished. An earlier image of this object — using less observation time and therefore not recording such faint detail — was published in 2009.

    During the cluster observations, Hubble also looked at six “parallel fields”, regions near the galaxy clusters which were imaged with the same exposure times as the clusters themselves. Each cluster and parallel field were imaged in infrared light by the Wide Field Camera 3 (WFC3), and in visible light by the Advanced Camera for Surveys (ACS).

    NASA/ESA Hubble WFC3

    NASA/ESA Hubble ACS

    The Frontier Fields programme produced the deepest observations ever made of galaxy clusters and the magnified galaxies behind them. These observations are helping astronomers understand how stars and galaxies emerged out of the dark ages of the Universe, when space was dark, opaque, and filled with hydrogen.

    Studying massive galaxy clusters like Abell 370 also helps with measuring the distribution of normal matter and dark matter within such clusters [heic1506]. By studying its lensing properties, astronomers have determined that Abell 370 contains two large, separate clumps of dark matter, contributing to the evidence that this massive galaxy cluster is actually the result of two smaller clusters merging together.

    Now that the observations for the Frontier Fields programme are complete, astronomers can use the full dataset to explore the clusters, their gravitational lensing effects and the magnified galaxies from the early Universe in full detail.

    Notes

    [1] Galaxy clusters are the most massive structures in the Universe that are held together by gravity, generally thought to have formed when smaller groups of galaxies smashed into each other in ever-bigger cosmic collisions. Such clusters can contain up to 1000 galaxies, along with hot intergalactic gas that often shines brightly at X-ray wavelengths, all bound together primarily by the gravity of dark matter.

    Links

    Images of Hubble
    Hubblesite release
    Frontier Fields

    See the full article here .

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    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 2:50 pm on April 20, 2017 Permalink | Reply
    Tags: , , , , Hubble observes first multiple images of explosive distance indicator, NASA ESA Hubble,   

    From Hubble: “Hubble observes first multiple images of explosive distance indicator” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope

    NASA/ESA Hubble Telescope

    20 April 2017
    Ariel Goobar
    Oskar Klein Centre at Stockholm University
    Stockholm, Sweden
    Tel: +46 8 5537 8659
    Email: ariel@fysik.su.se

    Rahman Amanullah
    Oskar Klein Centre at Stockholm University
    Stockholm, Sweden
    Tel: +46 8 5537 8848
    Email: rahman@fysik.su.se

    Mathias Jäger
    ESA/Hubble, Public Information Officer
    Garching bei München, Germany
    Tel: +49 176 62397500
    Email: mjaeger@partner.eso.org

    Lensed supernova will give insight into the expansion of the Universe

    1
    A Swedish-led team of astronomers used the NASA/ESA Hubble Space Telescope to analyse the multiple images of a gravitationally lensed type Ia supernova for the first time. The four images of the exploding star will be used to measure the expansion of the Universe. This can be done without any theoretical assumptions about the cosmological model, giving further clues about how fast the Universe is really expanding. The results are published in the journal Science.

    An international team, led by astronomers from the Stockholm University, Sweden, has discovered a distant type Ia supernova, called iPTF16geu [1] — it took the light 4.3 billion years to travel to Earth [2]. The light from this particular supernova was bent and magnified by the effect of gravitational lensing so that it was split into four separate images on the sky [3]. The four images lie on a circle with a radius of only about 3000 light-years around the lensing foreground galaxy, making it one of the smallest extragalactic gravitational lenses discovered so far. Its appearance resembles the famous Refsdal supernova, which astronomers detected in 2015 (heic1525). Refsdal, however, was a core-collapse supernova.

    1
    In November 2014, astronomers spotted the light from supernova Refsdal (yellow), which split into four images as it passed near an elliptical galaxy on its way to Earth.
    NASA / ESA / S. Rodney & FrontierSN /T. Treu / P. Kelly & GLASS / J. Lotz & Frontier Fields / M. Postman & CLASH / Z. Levay


    Hubblecast 70: Peering around cosmic corners

    Type Ia supernovae always have the same intrinsic brightness, so by measuring how bright they appear astronomers can determine how far away they are. They are therefore known as standard candles. These supernovae have been used for decades to measure distances across the Universe, and were also used to discover its accelerated expansion and infer the existence of dark energy. Now the supernova iPTF16geu allows scientists to explore new territory, testing the theories of the warping of spacetime on smaller extragalactic scales than ever before.

    “Resolving, for the first time, multiple images of a strongly lensed standard candle supernova is a major breakthrough. We can measure the light-focusing power of gravity more accurately than ever before, and probe physical scales that may have seemed out of reach until now,” says Ariel Goobar, Professor at the Oskar Klein Centre at Stockholm University and lead author of the study.

    The critical importance of the object meant that the team instigated follow-up observations of the supernova less than two months after its discovery. This involved some of the world’s leading telescopes in addition to Hubble: the Keck telescope on Mauna Kea, Hawaii, and ESO’s Very Large Telescope in Chile. Using the data gathered, the team calculated the magnification power of the lens to be a factor of 52. Because of the standard candle nature of iPTF16geu, this is the first time this measurement could be made without any prior assumptions about the form of the lens or cosmological parameters.

    Keck Observatory, Mauna Kea, Hawaii, USA

    ESO/VLT at Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level

    Currently the team is in the process of accurately measuring how long it took for the light to reach us from each of the four images of the supernova. The differences in the times of arrival can then be used to calculate the Hubble constant — the expansion rate of the Universe — with high precision [4]. This is particularly crucial in light of the recent discrepancy between the measurements of its value in the local and the early Universe (heic1702).

    As important as lensed supernovae are for cosmology, it is extremely difficult to find them. Not only does their discovery rely on a very particular and precise alignment of objects in the sky, but they are also only visible for a short time. “The discovery of iPTF16geu is truly like finding a somewhat weird needle in a haystack,” remarks Rahman Amanullah, co-author and research scientist at Stockholm University. “It reveals to us a bit more about the Universe, but mostly triggers a wealth of new scientific questions.”

    Studying more similarly lensed supernovae will help shape our understanding of just how fast the Universe is expanding. The chances of finding such supernovae will improve with the installation of new survey telescopes in the near future.
    Notes

    [1] iPTF16geu was initially observed by the iPTF (intermediate Palomar Transient Factory) collaboration with the Palomar Observatory. This is a fully automated, wide-field survey delivering a systematic exploration of the optical transient sky.

    Caltech Palomar Intermediate Palomar Transient Factory telescope at the Samuel Oschin Telescope at Palomar Observatory,located in San Diego County, California, United States

    [2] This corresponds to a redshift of 0.4. The lensing galaxy has a redshift of 0.2.

    [3] Gravitational lensing is a phenomenon that was first predicted by Albert Einstein in 1912. It occurs when a massive object lying between a distant light source and the observer bends and magnifies the light from the source behind it. This allows astronomers to see objects that would otherwise be to faint to see.

    [4] For each image of the supernova, the light is not bent in the same way. This results in slightly different travel times. The maximum time delay between the four images is predicted to be less than 35 hours.

    More information

    The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

    This research was presented in a paper entitled iPTF16geu: A multiply-imaged gravitationally lensed Type Ia supernova by Goobar et al., which appeared in the journal Science.

    The international team of astronomers in this study consists of A. Goobar (The Oskar Klein Centre, Sweden), R. Amanullah (The Oskar Klein Centre, Sweden), S. R. Kulkarni (Cahill Center for Astrophysics, USA), P. E. Nugent (University of California, USA; Lawrence Berkeley National Laboratory, USA), J. Johansson (Weizmann Institute of Science, Israel), C. Steidel (Cahill Center for Astrophysics, USA), D. Law (Space Telescope Science Institute, USA), E. Mörtsell (The Oskar Klein Centre, Sweden), R. Quimby (San Diego State University, USA; Kavli IPMU (WPI), Japan), N. Blagorodnova (Cahill Center for Astrophysics, USA), A. Brandeker (Stockholm University, Sweden), Y. Cao (eScience Institute and Department of Astronomy, USA), A. Cooray (University of California, USA), R. Ferretti (The Oskar Klein Centre, Sweden), C. Fremling (The Oskar Klein Centre, Sweden), L. Hangard (The Oskar Klein Centre, Sweden), M. Kasliwal (Cahill Center for Astrophysics, USA), T. Kupfer (Cahill Center for Astrophysics, USA), R. Lunnan (Cahill Center for Astrophysics, USA; Stockholm University, Sweden), F. Masci (Infrared Processing and Analysis Center, USA), A. A. Miller (Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA), USA; The Adler Planetarium, USA) H. Nayyeri (University of California, USA), J. D. Neill (Cahill Center for Astrophysics, USA), E. O. Ofek (Weizmann Institute of Science, Israel), S. Papadogiannakis (The Oskar Klein Centre, Sweden), T. Petrushevska (The Oskar Klein Centre, Sweden), V. Ravi (Cahill Center for Astrophysics, USA), J. Sollerman (The Oskar Klein Centre, Sweden), M. Sullivan (University of Southampton, UK), F. Taddia (The Oskar Klein Centre, Sweden), R. Walters (Cahill Center for Astrophysics, USA), D. Wilson (University of California, USA), L. Yan (Cahill Center for Astrophysics, USA), O. Yaron (Weizmann Institute of Science, Israel).

    Image credit: NASA, ESA, Sloan Digital Sky Survey, W. M. Keck Observatory, Palomar Observatory/California Institute of Technology

    See the full article here .

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    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 9:31 am on April 20, 2017 Permalink | Reply
    Tags: , , , , Hubble celebrates 27 years with two close friends, NASA ESA Hubble   

    From Hubble: “Hubble celebrates 27 years with two close friends” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope

    NASA/ESA Hubble Telescope

    Apr 20, 2017
    Ann Jenkins
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4488
    jenkins@stsci.edu

    Ray Villard
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4514
    villard@stsci.edu

    1
    Hubble Celebrates Its Anniversary with a Spectacular Pair of Galaxies
    When the Hubble Space Telescope launched aboard the Space Shuttle Discovery on April 24, 1990, astronomers could only dream what they might see. Now, 27 years and more than a million observations later, the telescope delivers yet another magnificent view of the universe — this time, a striking pair of spiral galaxies much like our own Milky Way. These island cities of stars, which are approximately 55 million light-years away, give astronomers an idea of what our own galaxy would look like to an outside observer. The edge-on galaxy is called NGC 4302, and the tilted galaxy is NGC 4298. Although the pinwheel galaxies look quite different because they are angled at different positions on the sky, they are actually very similar in terms of their structure and contents.

    From Hubble/ESA

    This stunning cosmic pairing of the two very different looking spiral galaxies NGC 4302 and NGC 4298 was imaged by the NASA/ESA Hubble Space Telescope. The image brilliantly captures their warm stellar glow and brown, mottled patterns of dust. As a perfect demonstration of Hubble’s capabilities, this spectacular view has been released as part of the telescope’s 27th anniversary celebrations.

    HUBBLE TRIVIA 2017

    Launched on April 24, 1990, NASA’s Hubble Space Telescope has made more than 1.3 million observations of more than 42,000 celestial objects.

    In its 27-year lifetime the telescope has made nearly 148,000 trips around our planet. Hubble has racked up plenty of frequent-flier miles, about 3.8 billion.
    An average of approximately 2 terabytes of Hubble data are added to the archive every month.

    Hubble observations have produced more than 141 terabytes of data, which will be available for present and future generations of researchers.
    Astronomers using Hubble data have published more than 14,600 scientific papers.

    HUBBLE HIGHLIGHTS

    An Accelerating Universe

    By capturing the glow from distant exploding stars, Hubble showed that the universe is expanding at an ever-faster rate. The acceleration may be caused by a mysterious “dark energy” that pervades the universe. Dark energy is a sort of “antigravity” that is pushing galaxies apart. Physicists regard dark energy as a total mystery, even though it comprises about 70 percent of the universe’s mass/energy budget. The researchers who made the Hubble discovery of the accelerating universe were awarded the 2011 Nobel Prize in Physics. By observing how dark energy behaves over time, astronomers hope to gain a better understanding of what it is and how it might affect the future of the universe.

    How Fast Is the Universe Expanding?

    Nearly a century ago, Edwin Hubble measured the expansion rate of the universe from its origin in the big bang. This value, called the Hubble constant, is an essential ingredient needed to determine the age, size, and fate of the universe. Astronomers using Hubble have refined their measurements of the universe’s current expansion rate to an uncertainty of just 2.4 percent — and are working to make it even more precise. The current value yields an age for the universe of 13.8 billion years old. Before Hubble was launched, the value for the Hubble constant was highly uncertain, and the calculations for the universe’s age ranged from 10 billion to 20 billion years.

    See feature article at https://www.nasa.gov/content/hubble-highlights-discovering-a-runaway-universe.

    Tracing the Growth of Galaxies

    Before Hubble’s launch, there was plenty of room for conjecture and theoretical modeling about how galaxies must evolve if the universe was born in the big bang. Ground-based observations were not able to establish which of several competing theories best described how galaxies formed and evolved in the early universe.

    Hubble’s powerful ability to detect galaxies that are much farther away than those ever seen before is allowing astronomers to trace the history of the universe. The deeper Hubble peers into space, the farther back in time it looks. The farthest galaxies detected by Hubble were forming just a few hundred million years after the big bang. Hubble’s visible “core sample” of the universe shows galaxies during their youth, providing evidence that galaxies grew over time through mergers with other galaxies to become the giant galaxies we see today. Young galaxies have close encounters that sometimes ended in grand mergers that yield overflowing sites of new star birth as the colliding galaxies morph into wondrous new shapes. The early galaxies spied by Hubble are smaller and more irregularly shaped than today’s grand spiral and elliptical galaxies. By studying galaxies at different epochs, astronomers can see how galaxies change over time. The process is analogous to a very large scrapbook of pictures documenting the lives of children from infancy to adulthood.

    And the evolution continues. Hubble observations of our neighboring galaxy, M31, has allowed astronomers to predict with certainty that titanic collision between our Milky Way galaxy Andromeda will inevitably take place beginning 4 billion years from now. The galaxy is now 2.5 million light-years away, but it is inexorably falling toward the Milky Way under the mutual pull of gravity between the two galaxies and the invisible dark matter that surrounds them both. The merger will result in the creation of a giant elliptical galaxy.

    See feature article at https://www.nasa.gov/content/hubble-highlights-tracing-the-growth-of-galaxies.

    Worlds Beyond Our Sun

    At the time of Hubble’s launch in 1990, astronomers had not found a single planet outside our solar system. Now there are more than 2,000 confirmed extrasolar planets, most of them discovered by NASA’s Kepler space observatory and by ground-based telescopes. Hubble, however, has made some unique contributions to the planet hunt.

    Astronomers used Hubble to make the first measurements of the atmospheric composition of extrasolar planets. The Hubble observations have identified atmospheres that contain sodium, oxygen, carbon, and hydrogen, and carbon dioxide, methane, and water vapor. The planets studied to date are too hot for life as we know it. But the Hubble observations demonstrate that the basic organic chemistry for life can be measured on planets orbiting other stars.

    Hubble also made one of the first visible-light images of an extrasolar planet circling the southern star Fomalhaut, located 25 light-years away. The unusual planet is following a highly elongated orbit and is now just inside the disk’s sharp inner edge, about 10 times the distance of Saturn from the sun.

    See feature article at https://www.nasa.gov/content/hubble-highlights-recognizing-worlds-beyond-our-sun.

    Shining a Light on Dark Matter

    Dark matter is an invisible form of matter that makes up most of the universe’s mass and forms its underlying structure. Dark matter’s gravity allows normal matter in the form of gas and dust to collect and build up into stars and galaxies. Although astronomers cannot see dark matter, they can detect its influence by observing how the gravity of massive galaxy clusters bends and distorts the light of more distant background galaxies, a phenomenon called gravitational lensing.

    Using Hubble’s sharp view, astronomers used the gravitational-lensing technique to construct the three-dimensional map by studying the warped images of half a million faraway galaxies. The new map provides the best evidence yet that normal matter, largely in the form of galaxies, accumulates along the densest concentrations of dark matter. The map stretches halfway back to the beginning of the universe and reveals a loose network of dark-matter filaments.

    See feature article at https://www.nasa.gov/content/hubble-highlights-shining-a-light-on-dark-matter.

    Monster Black Holes Are Everywhere

    Hubble provided decisive evidence that the hubs of most galaxies have mammoth black holes containing the mass of millions or even billions of stars. Not only are black holes residents in almost every galaxy, but they also have a tight relationship with their hosts. Hubble’s census of more than 30 galaxies showed that a black hole’s mass is dependent on the mass of its host galaxy’s central bulge of stars. Large galaxies have black holes that are proportionally more massive. This close relationship may be evidence that black holes grew along with their galaxies, devouring a fraction of the galaxy’s mass. The telescope also provided the first-ever views of disks of material encircling black holes.

    See feature article at https://www.nasa.gov/content/hubble-highlights-realizing-monster-black-holes-are-everywhere.

    Uncovering Icy Objects in the Kuiper Belt

    Probing the dwarf planet Pluto on the outskirts of our solar system, Hubble spied four new moons orbiting the icy world. Two of the moons are rotating chaotically as they orbit the dwarf planet.

    Peering out even farther, to the dim, outer reaches of our solar system, Hubble uncovered Kuiper Belt objects that the New Horizons spacecraft could potentially visit on the outbound leg of its tour of the solar system. The New Horizons spacecraft swung by Pluto in 2015, making detailed observations of the frigid dwarf planet. Hubble played a critical role in helping astronomers prepare for the New Horizons mission. With frequent observations of Pluto from the early 1990s to 2010, astronomers continued to refine maps of the planet’s surface. The maps were used as a guide for the July 2015 New Horizons flyby of the Pluto system.

    See feature article at https://www.nasa.gov/content/hubble-highlights-uncovering-icy-objects-in-the-kuiper-belt.

    Studying the Outer Planets and Moons

    Hubble witnessed impacts on Jupiter that were produced by minor bodies in the solar system. The latest collision occurred in 2009, when a suspected asteroid plunged into Jupiter’s atmosphere, leaving a temporary dark feature the size of the Pacific Ocean. In 1994 Hubble watched 21 fragments of comet Shoemaker-Levy 9 bombard the giant planet sequentially, the first time astronomers witnessed such an event. Each impact left temporary black, sooty scars in Jupiter’s planetary clouds.

    Jupiter is well known for its Great Red Spot, a giant storm roughly the size of the Earth that has been visible since the early 1800s. Astronomers have also used Hubble to measure the Great Red Spot’s downsizing. The mammoth storm has been shrinking in size for at least 80 years.

    Jupiter’s moons also have yielded important clues in the search for life beyond Earth. Hubble provided the best evidence yet for an underground saltwater ocean on Ganymede, the largest moon in the solar system. The subterranean ocean is thought to have more water than all the water on Earth’s surface. Hubble also caught plumes of water vapor erupting off the surface of Jupiter’s moon Europa. Astronomers do not yet know if these gas plumes are connected to subsurface liquid water. Identifying liquid water is crucial in the search for habitable worlds beyond Earth and for the search for life, as we know it.

    Hubble also made the first images of bright aurorae at the northern and southern poles of Saturn and Jupiter. Aurorae are brilliant curtains of light in the upper atmosphere of Saturn and Jupiter. They develop when electrically charged particles trapped in the magnetic field surrounding the planet spiral inward at high energies toward the north and south magnetic poles. When these particles hit the upper atmosphere, they excite atoms and molecules there, causing them to glow (the same process occurring in street lights).

    See feature article at https://www.nasa.gov/content/hubble-highlights-studying-the-outer-planets-and-moons.

    Evolution in the Asteroid Belt

    Asteroids don’t just slam into giant planets like Jupiter; they also collide with each other. Astronomers using Hubble witnessed one such smashup in the asteroid belt, a reservoir of leftover rubble from the construction of our solar system, located between Mars and Jupiter. The Hubble observations showed a bizarre X-shaped pattern of filamentary structures near the point-like core of the object and trailing streamers of dust. This complex structure suggests the small body is the product of a head-on collision between two asteroids traveling five times faster than a rifle bullet. Astronomers have long thought that the asteroid belt is being ground down through collisions, but such a smashup has never been seen before. Hubble also found evidence for asteroid disintegration.

    Another Hubble observation of the asteroid belt revealed a unique object: an asteroid with six comet-like tails of dust radiating from it like spokes on a wheel. Unlike all other known asteroids, which appear simply as tiny points of light, this asteroid resembles a rotating lawn sprinkler. Astronomers were surprised with the asteroid’s unusual appearance. Computer models of the object suggest that the tails could have been formed by a series of impulsive dust-ejection events.

    See feature article at https://www.nasa.gov/content/hubble-highlights-tracking-evolution-in-the-asteroid-belt.

    Planet Construction Zones

    Astronomers used Hubble to confirm that planets form in dust disks around stars. The telescope first resolved disks around nearly 200 stars in the nearby Orion Nebula. Looking at nearby stars, Hubble completed the largest and most sensitive visible-light imaging survey of dusty debris disks, which were probably created by collisions between leftover objects from planet formation. This survey yields insights into the birth of our own solar system. Hubble also spotted a mysterious gap in a vast protoplanetary disk of gas and dust swirling around TW Hydrae. The gap was most likely caused by a growing, unseen planet that is gravitationally sweeping up material and carving out a lane in the disk.

    See feature article at https://www.nasa.gov/content/hubble-highlights-finding-planetary-construction-zones.

    The Birth of Stars

    Hubble’s vision penetrated gigantic, turbulent clouds of gas and dust where tens of thousands of stars are bursting to life. Hubble images reveal a bizarre landscape sculpted by radiation from young, exceptionally bright stars. The observations reveal that star birth is a violent process of intense radiation and shock fronts. The intense ultraviolet radiation clears out cavities in stellar nurseries and erodes material from giant gas pillars that are incubators for fledgling stars.

    See feature article at https://www.nasa.gov/content/hubble-highlights-exploring-the-birth-of-stars.

    Going Out in a Blaze of Glory

    Hubble revealed unprecedented details of the death of Sun-like stars. Ground-based images suggested that many of these objects, called planetary nebulae, had simple spherical shapes. Hubble showed, however, that their shapes are more complex. Some look like pinwheels, others like butterflies, and still others like hourglasses. The images yield insights into the complex hydrodynamics that accompany a star’s shedding of its outer envelope before it collapses down to a white dwarf.

    Turning its vision to the tattered remains of a massive star’s explosive death, Hubble observations of Supernova 1987A revealed three mysterious rings of material encircling the doomed star. The telescope also spied brightened spots on the middle ring’s inner region, caused by an expanding wave of material from the explosion slamming into it.

    See feature article at https://www.nasa.gov/content/hubble-highlights-documenting-the-death-throes-of-stars.

    Credits

    NASA, ESA, and M. Mutchler (STScI)

    See the full article here .

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    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 12:58 pm on March 30, 2017 Permalink | Reply
    Tags: , , , , , NASA ESA Hubble,   

    From Hubble: “Search For Stellar Survivor of a Supernova Explosion ” Hubble-Europe and USA/HubbleSite 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope

    NASA/ESA Hubble Telescope

    You-Hua Chu
    Institute of Astronomy and Astrophysics, Academia Sinica
    Taipei, Taiwan
    Tel: +886 2 2366 5300
    Email: yhchu@asiaa.sincia.edu.tw

    Mathias Jäger
    ESA/Hubble, Public Information Officer
    Garching bei München, Germany
    Tel: +49 176 62397500
    Email: mjaeger@partner.eso.org

    Christine Pulliam
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-6437
    cpulliam@stsci.edu

    Ray Villard
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4514
    villard@stsci.edu

    1
    A group of astronomers used Hubble to study the remnant of the Type Ia supernova explosion SNR 0509-68.7 — also known as N103B (seen at the top). The supernova remnant is located in the Large Magellanic Cloud, just over 160 000 light-years from Earth.

    2
    This ground-based image shows both the Small and the Large Magellanic Clouds — two satellite galaxies of the Milky Way. The Small Magellanic Cloud can be seen on the left, the Large Magellanic Cloud on the right. This photo was taken by the Japanese astrophotographer Akira Fujii.

    In contrast to many other Supernova remnants N103B does not appear to have a spherical shape but is strongly elliptical. Astronomers assume that part of material ejected by the explosion hit a denser cloud of interstellar material, which slowed its speed. The shell of expanding material being open to one side supports this idea.

    The relative proximity of N103B allows astronomers to study the life cycles of stars in another galaxy in great detail. And probably even to lift the veil on questions surrounding this type of supernova. The predictable luminosity of Type Ia supernovae means that astronomers can use them as cosmic standard candles to measure their distances, making them useful tools in studying the cosmos. Their exact nature, however, is still a matter of debate. Astronomers suspect Type Ia supernovae occur in binary systems in which at least one of the stars in the pair is a white dwarf [1].

    There are currently two main theories describing how these binary systems become supernovae. Studies like the one that has provided the new image of N103B — that involve searching for remnants of past explosions — can help astronomers to finally confirm one of the two theories.

    One theory assumes that both stars in the binary are white dwarfs. If the stars merge with one another it would ultimately lead to a supernova explosion of type Ia.

    The second theory proposes that only one star in the system is a white dwarf, while its companion is a normal star. In this theory material from the companion star is accreted onto the white dwarf until its mass reaches a limit, leading to a dramatic explosion. In that scenario, the theory indicates that the normal star should survive the blast in at least some form. However, to date no residual companion around any type Ia supernova has been found.

    Astronomers observed the N103B supernova remnant in a search for such a companion. They looked at the region in H-alpha — which highlights regions of gas ionised by the radiation from nearby stars — to locate supernova shock fronts. They hoped to find a star near the centre of the explosion which is indicated by the curved shock fronts. The discovery of a surviving companion would put an end to the ongoing discussion about the origin of type Ia supernova.

    And indeed they found one candidate star that meets the criteria — for star type, temperature, luminosity and distance from the centre of the original supernova explosion. This star has approximately the same mass as the Sun, but it is surrounded by an envelope of hot material that was likely ejected from the pre-supernova system.

    Although this star is a reasonable contender for N103B’s surviving companion, its status cannot be confirmed yet without further investigation and a spectroscopic confirmation. The search is still ongoing.

    Notes

    [1] A white dwarf is the small, dense core of a medium-mass star that is left behind after it has reached the end of its main-sequence lifetime and blown off its outer layers. Our own Sun is expected to become a white dwarf in around five billion years.

    See the full article here .

    Please help promote STEM in your local schools.

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    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 3:45 pm on March 17, 2017 Permalink | Reply
    Tags: , , , Hubble Discovery of Runaway Star Yields Clues to Breakup of Multiple-Star System, NASA ESA Hubble   

    From Hubble: “Hubble Discovery of Runaway Star Yields Clues to Breakup of Multiple-Star System “ 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope

    NASA/ESA Hubble Telescope
    Mar 17, 2017

    Donna Weaver
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4493
    dweaver@stsci.edu

    Ray Villard
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4514
    villard@stsci.edu

    Kevin Luhman
    Penn State University, University Park, Pennsylvania
    kluhman@astro.psu.edu

    1
    Star Is Missing Link to a System that Flew Apart Over 500 Years Ago Credits NASA, ESA, K. Luhman (Penn State University), and M. Robberto (STScI)

    As British royal families fought the War of the Roses in the 1400s for control of England’s throne, a grouping of stars was waging its own contentious skirmish — a star wars far away in the Orion Nebula.

    The stars were battling each other in a gravitational tussle, which ended with the system breaking apart and at least three stars being ejected in different directions. The speedy, wayward stars went unnoticed for hundreds of years until, over the past few decades, two of them were spotted in infrared and radio observations, which could penetrate the thick dust in the Orion Nebula.

    The observations showed that the two stars were traveling at high speeds in opposite directions from each other. The stars’ origin, however, was a mystery. Astronomers traced both stars back 540 years to the same location and suggested they were part of a now-defunct multiple-star system. But the duo’s combined energy, which is propelling them outward, didn’t add up. The researchers reasoned there must be at least one other culprit that robbed energy from the stellar toss-up.

    Now NASA’s Hubble Space Telescope has helped astronomers find the final piece of the puzzle by nabbing a third runaway star. The astronomers followed the path of the newly found star back to the same location where the two previously known stars were located 540 years ago. The trio reside in a small region of young stars called the Kleinmann-Low Nebula, near the center of the vast Orion Nebula complex, located 1,300 light-years away.

    3
    Kleinmann-Low Nebula. NASA

    “The new Hubble observations provide very strong evidence that the three stars were ejected from a multiple-star system,” said lead researcher Kevin Luhman of Penn State University in University Park, Pennsylvania. “Astronomers had previously found a few other examples of fast-moving stars that trace back to multiple-star systems, and therefore were likely ejected. But these three stars are the youngest examples of such ejected stars. They’re probably only a few hundred thousand years old. In fact, based on infrared images, the stars are still young enough to have disks of material leftover from their formation.”

    All three stars are moving extremely fast on their way out of the Kleinmann-Low Nebula, up to almost 30 times the speed of most of the nebula’s stellar inhabitants. Based on computer simulations, astronomers predicted that these gravitational tugs-of-war should occur in young clusters, where newborn stars are crowded together. “But we haven’t observed many examples, especially in very young clusters,” Luhman said. “The Orion Nebula could be surrounded by additional fledging stars that were ejected from it in the past and are now streaming away into space.”

    The team’s results will appear in the March 20, 2017 issue of The Astrophysical Journal Letters.

    Luhman stumbled across the third speedy star, called “source x,” while he was hunting for free-floating planets in the Orion Nebula as a member of an international team led by Massimo Robberto of the Space Telescope Science Institute in Baltimore, Maryland. The team used the near-infrared vision of Hubble’s Wide Field Camera 3 to conduct the survey. During the analysis, Luhman was comparing the new infrared images taken in 2015 with infrared observations taken in 1998 by the Near Infrared Camera and Multi-Object Spectrometer (NICMOS). He noticed that source x had changed its position considerably, relative to nearby stars over the 17 years between Hubble images, indicating the star was moving fast, about 130,000 miles per hour.

    The astronomer then looked at the star’s previous locations, projecting its path back in time. He realized that in the 1470s source x had been near the same initial location in the Kleinmann-Low Nebula as two other runaway stars, Becklin-Neugebauer (BN) and “source I.”

    4
    BN. NASA

    BN was discovered in infrared images in 1967, but its rapid motion wasn’t detected until 1995, when radio observations measured the star’s speed at 60,000 miles per hour. Source I is traveling roughly 22,000 miles per hour. The star had only been detected in radio observations; because it is so heavily enshrouded in dust, its visible and infrared light is largely blocked.

    The three stars were most likely kicked out of their home when they engaged in a game of gravitational billiards, Luhman said. What often happens when a multiple system falls apart is that two of the member stars move close enough to each other that they merge or form a very tight binary. In either case, the event releases enough gravitational energy to propel all of the stars in the system outward. The energetic episode also produces a massive outflow of material, which is seen in the NICMOS images as fingers of matter streaming away from the location of the embedded source I star.

    Future telescopes, such as the James Webb Space Telescope, will be able to observe a large swath of the Orion Nebula. By comparing images of the nebula taken by the Webb telescope with those made by Hubble years earlier, astronomers hope to identify more runaway stars from other multiple-star systems that broke apart.

    See the full article here .

    Please help promote STEM in your local schools.

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    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 2:11 pm on March 9, 2017 Permalink | Reply
    Tags: , , , Hubble Dates Black Hole’s Last Big Meal, NASA ESA Hubble, ,   

    From Hubble: “Hubble Dates Black Hole’s Last Big Meal” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope

    NASA/ESA Hubble Telescope

    Mar 9, 2017

    Felicia Chou
    NASA Headquarters, Washington, D.C.
    felicia.chou@nasa.gov
    202-358-0257

    Donna Weaver / Ray Villard
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4493 / 410-338-4514
    dweaver@stsci.edu / villard@stsci.edu

    Rongmon Bordoloi
    Massachusetts Institute of Technology, Cambridge, Massachusetts
    617-252-1736
    bordoloi@mit.edu

    1
    Illustration Credit: NASA, ESA, and Z. Levy (STScI)

    For the supermassive black hole at the center of our Milky Way galaxy [Sag A*], it’s been a long time between dinners.


    Sag A* NASA Chandra X-Ray Observatory 23 July 2014, the supermassive black hole at the center of the Milky Way

    NASA’s Hubble Space Telescope has found that the black hole ate its last big meal about 6 million years ago, when it consumed a large clump of infalling gas. After the meal, the engorged black hole burped out a colossal bubble of gas weighing the equivalent of millions of suns, which now billows above and below our galaxy’s center.

    The immense structures, dubbed the Fermi Bubbles, were first discovered in 2010 by NASA’s Fermi Gamma-ray Space Telescope.


    NASA’s Fermi Gamma-ray Space Telescope

    But recent Hubble observations of the northern bubble have helped astronomers determine a more accurate age for the bubbles and how they came to be.

    “For the first time, we have traced the motion of cool gas throughout one of the bubbles, which allowed us to map the velocity of the gas and calculate when the bubbles formed,” said lead researcher Rongmon Bordoloi of the Massachusetts Institute of Technology in Cambridge. “What we find is that a very strong, energetic event happened 6 million to 9 million years ago. It may have been a cloud of gas flowing into the black hole, which fired off jets of matter, forming the twin lobes of hot gas seen in X-ray and gamma-ray observations. Ever since then, the black hole has just been eating snacks.”

    The new study is a follow-on to previous Hubble observations that placed the age of the bubbles at 2 million years old.

    A black hole is a dense, compact region of space with a gravitational field so intense that neither matter nor light can escape. The supermassive black hole at the center of our galaxy has compressed the mass of 4.5 million sun-like stars into a very small region of space.

    Material that gets too close to a black hole is caught in its powerful gravity and swirls around the compact powerhouse until it eventually falls in. Some of the matter, however, gets so hot it escapes along the black hole’s spin axis, creating an outflow that extends far above and below the plane of a galaxy.

    The team’s conclusions are based on observations by Hubble’s Cosmic Origins Spectrograph (COS), which analyzed ultraviolet light from 47 distant quasars. Quasars are bright cores of distant active galaxies.


    NASA Hubble Cosmic Origins Spectrograph

    Imprinted on the quasars’ light as it passes through the Milky Way bubble is information about the speed, composition, and temperature of the gas inside the expanding bubble.

    The COS observations measured the temperature of the gas in the bubble at approximately 17,700 degrees Fahrenheit. Even at those sizzling temperatures, this gas is much cooler than most of the super-hot gas in the outflow, which is 18 million degrees Fahrenheit, seen in gamma rays. The cooler gas seen by COS could be interstellar gas from our galaxy’s disk that is being swept up and entrained into the super-hot outflow. COS also identified silicon and carbon as two of the elements being swept up in the gaseous cloud. These common elements are found in most galaxies and represent the fossil remnants of stellar evolution.

    The cool gas is racing through the bubble at 2 million miles per hour. By mapping the motion of the gas throughout the structure, the astronomers estimated that the minimum mass of the entrained cool gas in both bubbles is equivalent to 2 million suns. The edge of the northern bubble extends 23,000 light-years above the galaxy.

    “We have traced the outflows of other galaxies, but we have never been able to actually map the motion of the gas,” Bordoloi said. “The only reason we could do it here is because we are inside the Milky Way. This vantage point gives us a front-row seat to map out the kinematic structure of the Milky Way outflow.”

    The new COS observations build and expand on the findings of a 2015 Hubble study by the same team, in which astronomers analyzed the light from one quasar that pierced the base of the bubble.

    “The Hubble data open a whole new window on the Fermi Bubbles,” said study co-author Andrew Fox of the Space Telescope Science Institute in Baltimore, Maryland. “Before, we knew how big they were and how much radiation they emitted; now we know how fast they are moving and which chemical elements they contain. That’s an important step forward.”

    The Hubble study also provides an independent verification of the bubbles and their origin, as detected by X-ray and gamma-ray observations.

    “This observation would be almost impossible to do from the ground because you need ultraviolet spectroscopy to detect the fingerprints of these elements, which can only be done from space,” Bordoloi said. “Only with COS do you have the wavelength coverage, the sensitivity, and the spectral resolution coverage to make this observation.”

    The Hubble results appeared in the January 10, 2017, edition of The Astrophysical Journal.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

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    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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