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  • richardmitnick 9:55 pm on May 5, 2014 Permalink | Reply
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    From NASA/Spitzer: “A Dusty View of Milky Ways Smaller Cousin” 2011 



    Spitzer

    This spectacular spiral galaxy is known to astronomers as Messier 83. Colloquially, it is also called the Southern Pinwheel due to its similarity to the more northerly Pinwheel galaxy Messier 101. NASAs Spitzer Space Telescope shows us, in spectacular detail, the infrared structure of what many think of as our own Milky Way galaxys smaller cousin.

    sp
    Credit NASA/JPL-Caltech
    Date 2011-11-23

    Another view, this from Hubble
    m
    NASA, ESA, and the Hubble Heritage Team (STScI/AURA) Acknowledgement: William Blair (Johns Hopkins University)

    Living in the middle of the Milky Ways disk, we see our galaxy only from an obstructed vantage point that is both inside-out and edge-on. We see Messier 83 nearly face-on, giving us a chance to really map out its disk in great detail. This information helps astronomers figure out what our own galaxy would look like if we could warp out to a better vantage point.

    Like the Milky Way, Messier 83 is classified as a barred spiral galaxy due to the bar-like pattern of stars that run through its center. This bar region is more interesting in the infrared since we can also see the open s shaped curve of dust (green) cutting through the more linear stellar bar (blue).

    This arc of inner dust connects up with the more tightly wound spiral arms in the outer disk, seen here as bright green-red ridges. Some of the hottest regions of star formation show up as reddish-white dots along the spiral arms, with the most vigorous star formation happening in the galaxys center. Between the main spiral arms we also see a complex webbing of dust that permeates the entire disk.

    While Messier 83 is about 15 million light years away, it is actually one of the closest barred spiral galaxies in the sky. This gives astronomers an excellent chance to study a galaxy that, although half as big, seems very similar in structure to our own Milky Way galaxy.

    Infrared light with wavelengths of 3.6 and 4.5 microns is shown as blue/cyan, showing primarily the glow from starlight. 8 micron light is rendered in green, and 24 micron emission is red, tracing the cooler and warmer components of dust, respectively.

    See the full article here.

    The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory located on the campus of the California Institute of Technology and part of NASA’s Infrared Processing and Analysis Center.
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  • richardmitnick 3:49 pm on April 25, 2014 Permalink | Reply
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    From NASA/Spitzer: “NASA’s Spitzer and WISE Telescopes Find Close, Cold Neighbor of Sun” 



    Spitzer

    NASA’s Wide-field Infrared Survey Explorer (WISE) and Spitzer Space Telescope have discovered what appears to be the coldest “brown dwarf” known — a dim, star-like body that surprisingly is as frosty as Earth’s North Pole.

    NASA Wise Telescope
    NASA/WISE

    bd
    WISE J085510.83-071442.5

    Images from the space telescopes also pinpointed the object’s distance to 7.2 light-years away, earning it the title for fourth closest system to our sun. The closest system, a trio of stars, is Alpha Centauri, at about 4 light-years away.

    ac
    Alpha Centauri

    cen
    Alpha Centauri Central

    “It’s very exciting to discover a new neighbor of our solar system that is so close,” said Kevin Luhman, an astronomer at Pennsylvania State University’s Center for Exoplanets and Habitable Worlds, University Park. “And given its extreme temperature, it should tell us a lot about the atmospheres of planets, which often have similarly cold temperatures.”

    Brown dwarfs start their lives like stars, as collapsing balls of gas, but they lack the mass to burn nuclear fuel and radiate starlight. The newfound coldest brown dwarf is named WISE J085510.83-071442.5. It has a chilly temperature between minus 54 and 9 degrees Fahrenheit (minus 48 to minus 13 degrees Celsius). Previous record holders for coldest brown dwarfs, also found by WISE and Spitzer, were about room temperature.

    WISE was able to spot the rare object because it surveyed the entire sky twice in infrared light, observing some areas up to three times. Cool objects like brown dwarfs can be invisible when viewed by visible-light telescopes, but their thermal glow — even if feeble — stands out in infrared light. In addition, the closer a body, the more it appears to move in images taken months apart. Airplanes are a good example of this effect: a closer, low-flying plane will appear to fly overhead more rapidly than a high-flying one.

    “This object appeared to move really fast in the WISE data,” said Luhman. “That told us it was something special.”

    After noticing the fast motion of WISE J085510.83-071442.5 in March of 2013, Luhman spent time analyzing additional images taken with Spitzer and the Gemini South telescope on Cerro Pachon in Chile. Spitzer’s infrared observations helped determine the frosty temperature of the brown dwarf. Combined detections from WISE and Spitzer, taken from different positions around the sun, enabled the measurement of its distance through the parallax effect. This is the same principle that explains why your finger, when held out right in front of you, appears to jump from side to side when you alternate left- and right-eye views.

    NOAO Gemini South
    Gemini South

    “It is remarkable that even after many decades of studying the sky, we still do not have a complete inventory of the sun’s nearest neighbors,” said Michael Werner, the project scientist for Spitzer at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. JPL manages and operates Spitzer. “This exciting new result demonstrates the power of exploring the universe using new tools, such as the infrared eyes of WISE and Spitzer.”

    WISE J085510.83-071442.5 is estimated to be 3 to 10 times the mass of Jupiter. With such a low mass, it could be a gas giant similar to Jupiter that was ejected from its star system. But scientists estimate it is probably a brown dwarf rather than a planet since brown dwarfs are known to be fairly common. If so, it is one of the least massive brown dwarfs known.

    In March of 2013, Luhman’s analysis of the images from WISE uncovered a pair of much warmer brown dwarfs at a distance of 6.5 light years, making that system the third closest to the sun. His search for rapidly moving bodies also demonstrated that the outer solar system probably does not contain a large, undiscovered planet, which has been referred to as “Planet X” or “Nemesis.”

    See the full article here.

    The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory located on the campus of the California Institute of Technology and part of NASA’s Infrared Processing and Analysis Center.
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  • richardmitnick 8:46 pm on April 2, 2014 Permalink | Reply
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    From NASA/Spitzer: “Spitzer Sees the Galactic Dawn with ‘Frontier Fields'” 



    Spitzer

    03.27.14
    No Writer Credit

    NASA’s Spitzer Space Telescope, in tandem with other major NASA observatories, has recently embarked on a major new mission to glimpse the universe’s very first galaxies. Called Frontier Fields, the project is a collaboration with the Hubble Space Telescope and the Chandra X-ray Observatory. All three telescopes, collectively known as NASA’s Great Observatories, are playing indispensable roles in this quest.

    NASA Frontier Fields

    NASA Hubble Telescope
    Hubble

    NASA Chandra Telescope
    Chandra

    The faintness of the earliest, most distant galaxies makes studying them a challenge. Frontier Fields, however, can spot these primordial galaxies courtesy of foreground clusters of galaxies, whose gargantuan mass and gravity form cosmic “zoom lenses.” Peering through these gravitational lenses is giving astronomers an unprecedented view of the galactic dawn.

    “Our overall science goal with the Frontier Fields is to understand how the first galaxies in the universe assembled,” said Peter Capak, a research scientist with the NASA/JPL Spitzer Science Center at the California Institute of Technology and the Spitzer lead for the Frontier Fields. “This pursuit is made possible by how massive galaxy clusters warp space around them, kind of like when you look through the bottom of a wine glass.”

    Although astronomers have relied on this cosmic lensing for many years now to turn up distant galactic quarry, Frontier Fields takes the practice to a new level. The project has selected the most massive and distant clusters on record, thus offering the highest magnification and deepest probe of the early universe available.

    Plus, Frontier Fields will further characterize the foreground clusters to better gauge the lenses’ magnifying, as well as distorting, effects. On average, the gravitational warping of space by foreground clusters magnifies background galaxies four to ten times. But some galaxies studied via Frontier Fields will be magnified on the order of a hundred times.

    NASA’s Great Observatories will view the cluster galaxies and background galaxies in different wavelengths of light, each of which carries important scientific information. Spitzer observes in longer wavelength, infrared light; Hubble, in shorter infrared and optical light; and Chandra in high-energy X-rays.

    The infrared light captured by Spitzer serves two key purposes. Firstly, infrared light is an indicator of the number of stars in a galaxy, which speaks to the galaxy’s overall mass. In the case of extremely distant galaxies, the optical light from their stars has been stretched out, or “redshifted,” into infrared wavelengths as a result of the expansion of the universe. “Spitzer basically measures the mass of galaxies,” said Capak. “Because of the wavelengths it works in, Spitzer is the only instrument capable of making mass measurements of galaxies this far away.”

    Secondly, Spitzer can help determine if certain galaxies also observed by Hubble are in fact the far-off, early galaxies of interest or just nearby galaxies. “Spitzer and Hubble can tell if galaxies discovered in the Frontier Fields are really at the edge of the universe or not,” said Capak.

    Hubble and Spitzer scientists envisioned this sort of synergy when the Frontier Fields were conceived in 2012. “This program exemplifies the combined strength of NASA’s Great Observatories when it comes to digging deep into the distant universe,” said Jennifer Lotz from the Space Telescope Science Institute, which manages Hubble for NASA.

    Chandra’s role in Frontier Fields, meanwhile, is to provide a detailed map of the hot, X-ray-emitting gas in the galaxy clusters. Doing so will help to further pin down their masses. Spitzer will be integral to this aspect of the project as well by presenting astronomers with an overview of the stars in the clusters’ galaxies.

    Observations of the first Frontier Field cluster, Abell 2744, have been completed. Work is now underway on another cluster and two more are slated for summer. The Abell 2744 effort has already resulted in the discovery of one of the most distant galaxies ever seen, dubbed Abell2744 Y1. This tiny, infant galaxy was witnessed at a time when the 13.8 billion-year-old universe was a mere 650 million years old. Frontier Fields is expected to reveal many other similarly primeval galaxies in the critical galaxy-forming epoch shortly after the Big Bang.

    Abell 2744
    NASA, ESA, J. Merten (Institute for Theoretical Astrophysics, Heidelberg/Astronomical Observatory of Bologna), and D. Coe (STScI)
    Date 22 June 2011
    Abell 2744, nicknamed Pandora’s Cluster. The galaxies in the cluster make up less than five percent of its mass. The gas (around 20 percent) is so hot that it shines only in X-rays (coloured red in this image). The distribution of invisible dark matter (making up around 75 percent of the cluster’s mass) is coloured here in blue.

    See the full article here.

    The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory located on the campus of the California Institute of Technology and part of NASA’s Infrared Processing and Analysis Center.
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  • richardmitnick 8:36 pm on March 24, 2014 Permalink | Reply
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    From ESA: “Star-forming region ON2″ 2010 

    ESASpaceForEuropeBanner
    European Space Agency

    Massive stars are born in tumultuous clouds of gas and dust. They lead a brief but intense life, blowing powerful winds of particles and radiation that strike their surroundings, before their explosive demise as supernovas.

    opn2
    ON2
    L.M. Oskinova, R.A. Gruendl, Spitzer Space Telescope, JPL, NASA & ESA
    Released 24/03/2014

    The interplay between massive stars and their environment is revealed in this image of the star-forming region ON2. It combines X-ray coverage from ESA’s XMM-Newton X-ray observatory with an infrared view from NASA’s Spitzer Space Telescope.

    ESA XMM Newton
    ESA XMM-newton

    NASA Spitzer Telescope
    NASA/Spitzer

    This stellar cradle is associated with the open cluster of stars named Berkeley 87, some 4000 light-years from Earth. The cluster is home to over 2000 stars, most of which are low-mass stars like our Sun or smaller, but some – a few dozen – are stellar monsters weighing 10–80 times more.

    Two glowing clouds of gas and dust – the raw material from which stars form – dominate the centre of the image and are shown in red. Scattered across the image are a multitude of protostars – seeds of future stellar generations; these are shown in green. The bright yellow star in the upper part of the image is BC Cygni, a massive star that has puffed up enormously and will eventually explode as a supernova.

    Shown in blue is XMM-Newton’s X-ray view of ON2: it reveals individual sources – young, massive stars as well as protostars – and more diffuse regions of X-rays. Two ‘bubbles’ of X-rays can be seen in the upper and lower clouds, respectively, pink against the red background. These two bubbles conceal the cumulative emissions from many protostars, but also light radiated by very energetic particles – a signature of shockwaves triggered by massive stars and their winds.

    The image combines observations performed in the X-ray energy range of 0.25–12 keV (blue) and at infrared wavelengths of 3.6 microns (green) and 8 microns (red). It spans about 15 arcminutes on each side; north is up and east is to the left.

    This image was first published in the paper Hard X-Ray Emission in the Star-Forming Region ON 2: Discovery with XMM-Newton by Oskinova et al. in April 2010.

    See the full article here.

    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

    ESA50 Logo large


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  • richardmitnick 5:59 pm on March 20, 2014 Permalink | Reply
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    From NASA/Spitzer: “NASA’s Spitzer Telescope Brings 360-Degree View of Galaxy to Our Fingertips “ 



    Spitzer

    03.20.14

    Touring the Milky Way now is as easy as clicking a button with NASA’s new zoomable, 360-degree mosaic presented Thursday at the TEDActive 2014 Conference in Vancouver, Canada.
    The star-studded panorama of our galaxy is constructed from more than 2 million infrared snapshots taken over the past 10 years by NASA’s Spitzer Space Telescope.

    mw

    “If we actually printed this out, we’d need a billboard as big as the Rose Bowl Stadium to display it,” said Robert Hurt, an imaging specialist at NASA’s Spitzer Space Science Center in Pasadena, Calif. “Instead, we’ve created a digital viewer that anyone, even astronomers, can use.”

    The 20-gigapixel mosaic uses Microsoft’s WorldWide Telescope visualization platform. It captures about three percent of our sky, but because it focuses on a band around Earth where the plane of the Milky Way lies, it shows more than half of all the galaxy’s stars.

    The image, derived primarily from the Galactic Legacy Mid-Plane Survey Extraordinaire project, or GLIMPSE, is online at: http://www.spitzer.caltech.edu/glimpse360

    Spitzer, launched into space in 2003 and has spent more than 10 years studying everything from asteroids in our solar system to the most remote galaxies at the edge of the observable universe. In this time, it has spent a total of 4,142 hours (172 days) taking pictures of the disk, or plane, of our Milky Way galaxy in infrared light. This is the first time those images have been stitched together into a single, expansive view.

    Our galaxy is a flat spiral disk; our solar system sits in the outer one-third of the Milky Way, in one of its spiral arms. When we look toward the center of our galaxy, we see a crowded, dusty region jam-packed with stars. Visible-light telescopes cannot look as far into this region because the amount of dust increases with distance, blocking visible starlight. Infrared light, however, travels through the dust and allows Spitzer to view past the galaxy’s center.

    “Spitzer is helping us determine where the edge of the galaxy lies,” said Ed Churchwell, co-leader of the GLIMPSE team at the University of Wisconsin-Madison. “We are mapping the placement of the spiral arms and tracing the shape of the galaxy.”

    Using GLIMPSE data, astronomers have created the most accurate map of the large central bar of stars that marks the center of the galaxy, revealing the Milky Way to be slightly larger than previously thought. GLIMPSE images have also shown a galaxy riddled with bubbles. These bubble structures are cavities around massive stars, which blast wind and radiation into their surroundings.

    All together, the data allow scientists to build a more global model of stars, and star formation in the galaxy — what some call the “pulse” of the Milky Way. Spitzer can see faint stars in the “backcountry” of our galaxy — the outer, darker regions that went largely unexplored before.

    “There are a whole lot more lower-mass stars seen now with Spitzer on a large scale, allowing for a grand study,” said Barbara Whitney of the University of Wisconsin-Madison, co-leader of the GLIMPSE team. “Spitzer is sensitive enough to pick these up and light up the entire ‘countryside’ with star formation.”

    The Spitzer team previously released an image compilation showing 130 degrees of our galaxy, focused on its hub. The new 360-degree view will guide NASA’s upcoming James Webb Space Telescope to the most interesting sites of star-formation, where it will make even more detailed infrared observations.

    NASA Webb Telescope
    James Webb Space Telescope

    Some sections of the GLIMPSE mosaic include longer-wavelength data from NASA’s Wide-field Infrared Survey Explorer, or WISE, which scanned the whole sky in infrared light.

    NASA Wise Telescope
    NASA/WISE

    The GLIMPSE data are also part of a citizen science project, where users can help catalog bubbles and other objects in our Milky Way galaxy. To participate, visit: http://www.milkywayproject.org

    See the full article here.

    The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory located on the campus of the California Institute of Technology and part of NASA’s Infrared Processing and Analysis Center.
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  • richardmitnick 8:07 am on March 16, 2014 Permalink | Reply
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    From ESA: “Eye-catching celestial helix” 2003 

    ESASpaceForEuropeBanner
    European Space Agency

    29/04/2003

    In one of the largest and most detailed celestial images ever, astronomers today unveil the coil-shaped Helix Nebula to celebrate Astronomy Day.

    helix
    Credit: NASA, NOAO, ESA, the Hubble Helix Nebula Team, M. Meixner (STScI), and T.A. Rector (NRAO)
    Instrument ACS

    NASA Hubble ACS
    Advanced Camera for Surveys

    This ESA/NASA Hubble Space Telescope image shows a fine web of filamentary ‘bicycle-spoke’ features embedded in the colourful red and blue gas ring, which is one of the nearest planetary nebulae to Earth. The nebula is nearby so it is nearly half the size of the diameter of the full Moon. Hubble astronomers took several exposures with the Advanced Camera for Surveys to capture most of it. They then combined Hubble views with a wider photo taken by Kitt Peak’s Mosaic Camera.

    mosaic
    Mosiac

    Another view
    ano
    This infrared image from NASA’s Spitzer Space Telescope shows the Helix Nebula, a cosmic starlet often photographed by amateur astronomers for its vivid colors and eerie resemblance to a giant eye.

    The nebula, located about 700 light-years away in the constellation Aquarius, belongs to a class of objects called planetary nebulae. Discovered in the 18th century, these colorful beauties were named for their resemblance to gas-giant planets like Jupiter.

    Planetary nebulae are the remains of stars that once looked a lot like our sun. When sun-like stars die, they puff out their outer gaseous layers. These layers are heated by the hot core of the dead star, called a white dwarf, and shine with infrared and visible colors. Our own sun will blossom into a planetary nebula when it dies in about five billion years.

    In Spitzer’s infrared view of the Helix nebula, the eye looks more like that of a green monster’s. Infrared light from the outer gaseous layers is represented in blues and greens. The white dwarf is visible as a tiny white dot in the center of the picture. The red color in the middle of the eye denotes the final layers of gas blown out when the star died.

    The brighter red circle in the very center is the glow of a dusty disk circling the white dwarf (the disk itself is too small to be resolved). This dust, discovered by Spitzer’s infrared heat-seeking vision, was most likely kicked up by comets that survived the death of their star. Before the star died, its comets and possibly planets would have orbited the star in an orderly fashion. But when the star blew off its outer layers, the icy bodies and outer planets would have been tossed about and into each other, resulting in an ongoing cosmic dust storm. Any inner planets in the system would have burned up or been swallowed as their dying star expanded.

    So far, the Helix nebula is one of only a few dead-star systems in which evidence for comet survivors has been found.
    This image is made up of data from Spitzer’s infrared array camera and multiband imaging photometer. Blue shows infrared light of 3.6 to 4.5 microns; green shows infrared light of 5.8 to 8 microns; and red shows infrared light of 24 microns.

    See the full article here.

    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.


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  • richardmitnick 4:57 pm on March 10, 2014 Permalink | Reply
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    A Tour of “GOODS” – Video About the Many Telescopes Needed for Great Astronomy 

    Please enjoy the video. Goods is Great Observatories Origins Deep Survey

    ESO VLT
    ESO VLT

    NASA Hubble Space Telescope
    NASA/ESA Hubble

    NASA Spitzer Telescope
    NASA Spitzer

    NASA Chandra Telescope
    NASA Chandra

    ESO APEX
    ESO APEX

    ESO ALMA Array
    ESO/ NAOJ/ NRAO ALMA

    ESO 50 Large

    NASA


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  • richardmitnick 1:13 pm on March 6, 2014 Permalink | Reply
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    From NASA/Spitzer: “Mystery of Planet-forming Disks Explained by Magnetism” 



    Spitzer

    03.06.14
    No Writer Credit

    Astronomers say that magnetic storms in the gas orbiting young stars may explain a mystery that has persisted since before 2006.

    formation

    Researchers using NASA’s Spitzer Space Telescope to study developing stars have had a hard time figuring out why the stars give off more infrared light than expected. The planet-forming disks that circle the young stars are heated by starlight and glow with infrared light, but Spitzer detected additional infrared light coming from an unknown source.

    A new theory, based on three-dimensional models of planet-forming disks, suggests the answer: Gas and dust suspended above the disks on gigantic magnetic loops like those seen on the sun absorb the starlight and glow with infrared light.

    “If you could somehow stand on one of these planet-forming disks and look at the star in the center through the disk atmosphere, you would see what looks like a sunset,” said Neal Turner of NASA’s Jet Propulsion Laboratory, Pasadena, Calif.

    The new models better describe how planet-forming material around stars is stirred up, making its way into future planets, asteroids and comets.

    While the idea of magnetic atmospheres on planet-forming disks is not new, this is the first time they have been linked to the mystery of the observed excess infrared light. According to Turner and colleagues, the magnetic atmospheres are similar to what takes place on the surface of our sun, where moving magnetic field lines spur tremendous solar prominences to flare up in big loops.

    Stars are born out of collapsing pockets in enormous clouds of gas and dust, rotating as they shrink down under the pull of gravity. As a star grows in size, more material rains down toward it from the cloud, and the rotation flattens this material out into a turbulent disk. Ultimately, planets clump together out of the disk material.

    In the 1980s, the Infrared Astronomical Satellite mission, a joint project that included NASA, began finding more infrared light than expected around young stars. Using data from other telescopes, astronomers pieced together the presence of dusty disks of planet-forming material. But eventually it became clear the disks alone weren’t enough to account for the extra infrared light — especially in the case of stars a few times the mass of the sun.

    One theory introduced the idea that instead of a disk, the stars were surrounded by a giant dusty halo, which intercepted the star’s visible light and re-radiated it at infrared wavelengths. Then, recent observations from ground-based telescopes suggested that both a disk and a halo were needed. Finally, three-dimensional computer modeling of the turbulence in the disks showed the disks ought to have fuzzy surfaces, with layers of low-density gas supported by magnetic fields, similar to the way solar prominences are supported by the sun’s magnetic field.

    The new work brings these pieces together by calculating how the starlight falls across the disk and its fuzzy atmosphere. The result is that the atmosphere absorbs and re-radiates enough to account for all the extra infrared light.

    “The starlight-intercepting material lies not in a halo, and not in a traditional disk either, but in a disk atmosphere supported by magnetic fields,” said Turner. “Such magnetized atmospheres were predicted to form as the disk drives gas inward to crash onto the growing star.”

    Over the next few years, astronomers will further test these ideas about the structure of the disk atmospheres by using giant ground-based telescopes linked together as interferometers. An interferometer combines and processes data from multiple telescopes to show details finer than each telescope can see alone. Spectra of the turbulent gas in the disks will also come from NASA’s SOFIA telescope, the Atacama Large Millimeter/submillimeter Array (ALMA) telescope in Chile, and from NASA’s James Webb Space Telescope after its launch in 2018.

    See the full article here.

    The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory located on the campus of the California Institute of Technology and part of NASA’s Infrared Processing and Analysis Center.
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  • richardmitnick 3:25 pm on February 26, 2014 Permalink | Reply
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    From NASA/Spitzer: “Spitzer Stares into the Heart of New Supernova in M82″ 



    Spitzer

    February 26, 2014
    Whitney Clavin 818-354-4673
    Jet Propulsion Laboratory, Pasadena, Calif.
    whitney.clavin@jpl.nasa.gov

    The closest supernova of its kind to be observed in the last few decades has sparked a global observing campaign involving legions of instruments on the ground and in space, including NASA’s Spitzer Space Telescope. With its dust-piercing infrared vision, Spitzer brings an important perspective to this effort by peering directly into the heart of the aftermath of the stellar explosion.

    m82
    The closest supernova of its kind to be observed in the last few decades has sparked a global observing campaign involving legions of instruments on the ground and in space, including NASA’s Spitzer Space Telescope. Image Credit: NASA/JPL-Caltech/Carnegie Institution for Science

    Dust in the supernova’s host galaxy M82, also called the “Cigar galaxy,” partially obscures observations in optical and high-energy forms of light. Spitzer can, therefore, complement all the other observatories taking part in painting a complete portrait of a once-in-a-generation supernova, which was first spotted in M82 on Jan. 21, 2014. A supernova is a tremendous explosion that marks the end of life for some stars.

    Another view of M82
    m82a
    This is a composite image made from three satellite observation projects. Visible aspects of the galaxy were taken by the HST. It is also shown in invisible infrared and X-ray spectrums: Spitzer photographed it in infrared, which shows dust emission, and Chandra photographed it in X-ray (showing mostly synchrotron emissions from fast electrons). The X-ray emission is shown in the blue parts.

    “At this point in the supernova’s evolution, observations in infrared let us look the deepest into the event,” said Mansi Kasliwal, Hubble Fellow and Carnegie-Princeton Fellow at the Observatories of the Carnegie Institution for Science and the principal investigator for the Spitzer observations. “Spitzer is really good for bypassing the dust and nailing down what’s going on in and around the star system that spawned this supernova.”

    Supernovas are among the most powerful events in the universe, releasing so much energy that a single outburst can outshine an entire galaxy. The new supernova, dubbed SN 2014J, is of a particular kind known as a Type Ia. This type of supernova results in the complete destruction of a white dwarf star-the small, dense, aged remnant of a typical star like our sun. Two scenarios are theorized to give rise to Type Ia supernovas. First, in a binary star system, a white dwarf gravitationally pulls in matter from its companion star, accruing mass until the white dwarf crosses a critical threshold and blows up. In the second, two white dwarfs in a binary system spiral inward toward each other and eventually collide explosively.

    sn2014j
    SN 2014J

    Type Ia supernovas serve a critically important role in gauging the expansion of the universe because they explode with almost exactly the same amount of energy, shining with a near-uniform peak brightness. The fainter a Type Ia supernova looks from our vantage point, the farther away it must be. Accordingly, Type Ia supernovas are referred to as “standard candles,” which allow astronomers to pin down the distances to nearby galaxies. Studying SN 2014J will help with understanding the processes behind Type Ia detonations to further refine theoretical models.

    Fortuitously, Spitzer had already been scheduled to observe M82 on January 28, a week after students and staff from University College London first spotted SN 2014J on Jan. 21. Subsequent observations, also part of Kasliwal’s SPIRITS (SPitzer InfraRed Intensive Transients Survey) program, took place on Feb. 7, 12, 19 and 24 and are slated for March 3.

    The supernova is glowing very brightly in the infrared light that Spitzer sees. The telescope was able to observe the supernova before and after it reached its peak brightness. Such early observations with an infrared telescope have only been obtained for a few Type Ia supernovas in the past. Researchers are currently using the data to learn more about how these explosions occur.

    Among the other major space-based observatories used in the M82 viewing campaign are NASA’s Hubble Space Telescope, Chandra X-ray Observatory, Nuclear Spectroscopic Telescope Array (NuSTAR), Fermi Gamma-ray Space Telescope, and Swift Gamma Ray Burst Explorer. In addition to Spitzer, key infrared observations are being collected by the airplane-borne Stratospheric Observatory for Infrared Astronomy (SOFIA).

    See the full article here.

    The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory located on the campus of the California Institute of Technology and part of NASA’s Infrared Processing and Analysis Center.
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  • richardmitnick 10:41 pm on February 21, 2014 Permalink | Reply
    Tags: , , , , NASA Spitzer   

    From NASA/Spitzer: “The Shocking Behavior of a Speedy Star” 



    Spitzer

    February 20, 2014

    Whitney Clavin 818-354-4673
    Jet Propulsion Laboratory, Pasadena, Calif.
    whitney.clavin@jpl.nasa.gov

    Roguish runaway stars can have a big impact on their surroundings as they plunge through the Milky Way galaxy. Their high-speed encounters shock the galaxy, creating arcs, as seen in this newly released image from NASA’s Spitzer Space Telescope.

    runaway
    The red arc in this infrared image from NASA’s Spitzer Space Telescope is a giant shock wave, created by a speeding star known as Kappa Cassiopeiae. Image credit: NASA/JPL-Caltech

    In this case, the speedster star is known as Kappa Cassiopeiae, or HD 2905 to astronomers. It is a massive, hot supergiant moving at around 2.5 million mph relative to its neighbors (1,100 kilometers per second). But what really makes the star stand out in this image is the surrounding, streaky red glow of material in its path. Such structures are called bow shocks, and they can often be seen in front of the fastest, most massive stars in the galaxy.

    Bow shocks form where the magnetic fields and wind of particles flowing off a star collide with the diffuse, and usually invisible, gas and dust that fill the space between stars. How these shocks light up tells astronomers about the conditions around the star and in space. Slow-moving stars like our sun have bow shocks that are nearly invisible at all wavelengths of light, but fast stars like Kappa Cassiopeiae create shocks that can be seen by Spitzer’s infrared detectors.

    Incredibly, this shock is created about 4 light-years ahead of Kappa Cassiopeiae, showing what a sizable impact this star has on its surroundings. (This is about the same distance that we are from Proxima Centauri, the nearest star beyond the sun.)

    The Kappa Cassiopeiae bow shock shows up as a vividly red color. The faint green features in this image result from carbon molecules, called polycyclic aromatic hydrocarbons, in dust clouds along the line of sight that are illuminated by starlight.

    Delicate red filaments run through this infrared nebula, crossing the bow shock. Some astronomers have suggested these filaments may be tracing out features of the magnetic field that runs throughout our galaxy. Since magnetic fields are completely invisible themselves, we rely on chance encounters like this to reveal a little of their structure as they interact with the surrounding dust and gas.

    Kappa Cassiopeiae is visible to the naked eye in the Cassiopeia constellation (but its bow shock only shows up in infrared light.)

    For this Spitzer image, infrared light at wavelengths of 3.6 and 4.5 microns is rendered in blue, 8.0 microns in green, and 24 microns in red.

    See the full article here.

    The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory located on the campus of the California Institute of Technology and part of NASA’s Infrared Processing and Analysis Center.
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