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Supernova Shock Wave Paints
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| Title |
Supernova Shock Wave Paints Cosmic Portrait |
| General Information |
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. Back to top [ #top ] |
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Supernova Shock Wave Paints
…
| Title |
Supernova Shock Wave Paints Cosmic Portrait |
| General Information |
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. Back to top [ #top ] |
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Supernova Shock Wave Paints
…
| Title |
Supernova Shock Wave Paints Cosmic Portrait |
| General Information |
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. Back to top [ #top ] |
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Supernova Shock Wave Paints
…
| Title |
Supernova Shock Wave Paints Cosmic Portrait |
| General Information |
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. Back to top [ #top ] |
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Giant Cluster Bends, Breaks
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| Title |
Giant Cluster Bends, Breaks Images |
| Explanation |
What are those strange blue objects? Many are images of a "single," unusual, beaded, blue, ring-like galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap981219.html ] which just happens to line-up behind a giant cluster of galaxies. [ http://antwrp.gsfc.nasa.gov/apod/clusters_of_galaxies.html ] Cluster galaxies here appear yellow and -- together with the cluster's dark matter [ http://antwrp.gsfc.nasa.gov/apod/ap960419.html ] -- act as a gravitational lens [ http://antwrp.gsfc.nasa.gov/apod/ap951220.html ]. A gravitational lens [ http://cfa-www.harvard.edu/~jcohn/lens.html ] can create several images of background galaxies, analogous to the many points of light one would see while looking through a wine glass [ http://vela.astro.ulg.ac.be/themes/extragal/gravlens/bibdat/engl/DE/didac.html ] at a distant street light. The distinctive shape of this background galaxy [ http://www.journals.uchicago.edu/ApJ/journal/issues/ApJL/v461n2/5782/5782.html ] -- which is probably just forming -- has allowed astronomers to deduce that it has separate images at 4, 8, 9 and 10 o'clock, from the center of the cluster. Possibly even the blue smudge just left of center is yet another image! This spectacular photo from the Hubble Space Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap970306.html ] was taken in October 1994. |
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Illusion and Evolution in Ga
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| Title |
Illusion and Evolution in Galaxy Cluster Abell 2667 |
| Explanation |
What's happening to the galaxies of cluster Abell 2667? On the upper left, a galaxy appears to be breaking up into small pieces, while on the far right, another galaxy appears to be stretched like taffy. To start, most of the yellowish objects in the above image [ http://www.spacetelescope.org/news/html/heic0705.html ] from the Hubble Space Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap010806.html ] are galactic members of a massive cluster of galaxies [ http://antwrp.gsfc.nasa.gov/apod/clusters_of_galaxies.html ] known as Abell 2667 [ http://en.wikipedia.org/wiki/Abell_2667 ]. The distortion of the galaxy on the upper left is real. As the galaxy plows through the intercluster medium [ http://www.physicsforums.com/archive/index.php/t-77572.html ], gas is stripped out and condenses to form bright new knots of stars. This detailed image of ram pressure [ http://en.wikipedia.org/wiki/Ram_pressure ] stripping helps astronomers understand why so many galaxies today have so little gas. The distortion of the galaxy on the far right, however, is an illusion [ http://en.wikipedia.org/wiki/Optical_illusion ]. This nearly normal galaxy is actually far behind the massive galaxy cluster. Light from this galaxy is gravitationally lensed [ http://www.astro.ucla.edu/~wright/cluster-lensing.html ] by Abell 2667, appearing much like a distant person would appear through [ http://vela.astro.ulg.ac.be/themes/extragal/gravlens/bibdat/engl/DE/didac.html ] a wine glass. Each distorted galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap040807.html ] gives important clues about how galaxies and clusters of galaxies evolve [ http://en.wikipedia.org/wiki/Galaxy_formation_and_evolution ]. |
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Simulated Galaxy Cluster Vie
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| Title |
Simulated Galaxy Cluster View |
| Explanation |
Stunningly detailed, this picture is a computer simulated view [ http://oposite.stsci.edu/pubinfo/pr/2002/06/ index.html ] of a cluster of galaxies [ http://antwrp.gsfc.nasa.gov/apod/ clusters_of_galaxies.html ] in the distant cosmos [ http://archive.ncsa.uiuc.edu/Cyberia/Cosmos/ HierarchUni.html ]. A large, elliptical galaxy dominates this hypothetical cluster's central region surrounded by a swarm of member galaxies. Other galaxies which lie far behind the cluster are seen as numerous visible concentric arcs [ http://antwrp.gsfc.nasa.gov/apod/ap011007.html ] - lensed by [ http://www.iam.ubc.ca/~newbury/lenses/ research.html ] the enormous gravitational [ http://vela.astro.ulg.ac.be/themes/extragal/gravlens/ bibdat/ ] field dominated by dark matter [ http://antwrp.gsfc.nasa.gov/apod/ap011024.html ] within the cluster itself. Such magnificent images are expected to be achieved by the Advanced Camera for Surveys [ http://www.ball.com/aerospace/acs.html ] (ACS), one of the upgrades [ http://sm3b.gsfc.nasa.gov/mission-critical/ objectives-part1.html ] being installed on the Hubble Space Telescope during the ongoing servicing mission [ http://spaceflight.nasa.gov/shuttle/crew/grunsfeldreports/ grunsfeldreports.html ]. Compared to Hubble's workhorse Wide Field Planetary Camera 2 [ http://hubble.stsci.edu/sci.d.tech/behind_the_pictures/ wacky_shape/constructing.shtml ] (WFPC2), whose achievements include the current deep field views [ http://www.stsci.edu/ftp/science/hdf/hdf.html ] of the Universe, the new technology ACS will be twice as sharp an imager with twice the field of view and five times the sensitivity. Along with extended views of the distant cosmos, enthusiastic astronomers also plan to use the ACS to monitor our own Solar System [ http://antwrp.gsfc.nasa.gov/apod/ap020214.html ] and to search for planets orbiting stars [ http://www.generation.net/~mariob/astro/exoplan/ intro-e.htm ] beyond the Sun. |
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The Pencil Nebula Supernova
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| Title |
The Pencil Nebula Supernova Shockwave |
| Explanation |
At 500,000 kilometers per hour, a supernova [ http://heasarc.gsfc.nasa.gov/docs/snr.html ] shockwave [ http://www.sciam.com/article.cfm?articleID=0004A908-9AAC-1CDC-B4A8809EC588EEDF ] plows through interstellar space. This shockwave is known as the Pencil Nebula [ http://www.ast.cam.ac.uk/AAO/images/captions/aat084.html ], or NGC 2736, and is part of the Vela supernova remnant [ http://antwrp.gsfc.nasa.gov/apod/ap960612.html ], an expanding shell of a star that exploded about 11,000 years ago. Initially the shockwave [ http://heritage.stsci.edu/2003/16/caption.html ] was moving at millions of kilometers per hour, but the weight of all the gas it has swept up has slowed it considerably. Pictured above [ http://hubblesite.org/newscenter/archive/2003/16/image/a ], the shockwave [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2003ApJ...589..242S ] moves from left to right, as can be discerned by the lack of gas on the left. The above region [ http://heritage.stsci.edu/2003/16/fast_facts.html ] spans nearly a light year [ http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question19.html ] across, a small part of the 100+ light-year span of the entire Vela supernova remnant [ http://antwrp.gsfc.nasa.gov/apod/ap990803.html ]. The Hubble Space Telscope [ http://antwrp.gsfc.nasa.gov/apod/ap010806.html ] ACS [ http://acs.pha.jhu.edu/ ] captured the above image last October. |
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Composite Crab
| Title |
Composite Crab |
| Explanation |
The Crab Pulsar, a city-sized, magnetized neutron star [ http://antwrp.gsfc.nasa.gov/apod/ap030201.html ] spinning 30 times a second, lies at the center of this composite image of the inner region of the well-known Crab Nebula [ http://www.seds.org/messier/m/m001.html ]. The spectacular picture combines optical data (red) from the Hubble Space Telescope [ http://hubblesite.org/gallery/ ] and x-ray images (blue) from the Chandra Observatory [ http://chandra.harvard.edu/chronicle/0303/top_ten/ ], also used in the popular Crab Pulsar movies [ http://chandra.harvard.edu/photo/2002/0052/movies.html ]. Like a cosmic dynamo [ http://chandra.harvard.edu/chronicle/0201/vela.html ] the pulsar powers [ http://antwrp.gsfc.nasa.gov/apod/ap010602.html ] the x-ray and optical emission from the nebula, accelerating charged particles and producing the eerie, glowing x-ray jets. Ring-like structures are x-ray emitting regions where the high energy particles slam into the nebular material. The innermost ring is about a light-year across. With more mass than the Sun [ http://www.sunblock99.org.uk/sb99/fact/heavy.html ] and the density of an atomic nucleus [ http://hyperphysics.phy-astr.gsu.edu/hbase/ nuclear/nucuni.html#c2 ], the spinning pulsar is the collapsed core of a massive star that exploded, while the nebula is the expanding remnant of the star's outer layers. The supernova explosion was witnessed in the year 1054 [ http://www.seds.org/messier/more/m001_sn.html ]. |
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Abell 2218: A Galaxy Cluster
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| Title |
Abell 2218: A Galaxy Cluster Lens |
| Explanation |
Gravity can bend light [ http://antwrp.gsfc.nasa.gov/apod/ap951126.html ]. Almost all of the bright objects in this Hubble Space Telescope image [ http://oposite.stsci.edu/pubinfo/PR/95/14.html ] are galaxies in the cluster known as Abell 2218. The cluster is so massive and so compact that its gravity bends and focuses the light [ http://vela.astro.ulg.ac.be/themes/extragal/gravlens/ bibdat/engl/glc_homepage.html ] from galaxies that lie behind it. As a result, multiple images of these background galaxies [ http://antwrp.gsfc.nasa.gov/apod/ap951220.html ] are distorted into faint stretched out arcs - a simple lensing effect analogous to viewing distant street lamps through a glass of wine. The Abell 2218 cluster itself is about 3 billion light-years away in the northern constellation Draco [ http://astro.gmu.edu/constellation/DRA.html ]. |
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A Bulls-Eye Einstein Ring
| Title |
A Bulls-Eye Einstein Ring |
| Explanation |
Can one galaxy hide behind another? Not in the case of B1938+666 [ http://www.jb.man.ac.uk/ceres/1938/1938.html ]. Here the foreground galaxy acts like a huge gravitational lens [ http://antwrp.gsfc.nasa.gov/apod/ap970503.html ], pulling the light from the background object around it, keeping it visible. Here the alignment is so precise that the distant galaxy is distorted into a nearly perfect giant ring around the foreground galaxy, a formation known as an Einstein ring [ http://www.iam.ubc.ca/spider/newbury/lenses/Einstein_rings.html ]. The bright peak at the center of the bulls-eye is the nearer galaxy. The cosmic mirage [ http://vela.astro.ulg.ac.be/themes/extragal/gravlens/bibdat/engl/index.html ] was found initially with the MERLIN radio telescope array [ http://www.jb.man.ac.uk/merlin/about/layman/merlin.html ]. The follow-up image shown above from the Hubble Space Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap950810.html ] was released [ http://www.jb.man.ac.uk/merlin/press/PR9801/press.html ] earlier today. Although appearing extremely small at 1 arcsecond [ http://proxima.astro.virginia.edu/~pai/Text/coords/subsection4_1.html ] diameter, the above Einstein ring [ http://antwrp.gsfc.nasa.gov/htmltest/gifcity/nslens_effects.html ] is really tens of thousands of light years across. |
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PG 1115+080 A Ghost of Lensi
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| Title |
PG 1115+080 A Ghost of Lensing Past |
| Explanation |
In this tangle of quasars and galaxies lies a clue to the expansion rate of the universe. A diffuse glow evident in the picture on the left reveals a normal elliptical galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap961106.html ]. Directly behind this galaxy lies a normal quasar [ http://antwrp.gsfc.nasa.gov/apod/ap980409.html ]. Because the quasar [ http://antwrp.gsfc.nasa.gov/apod/ap971206.html ] is directly behind the galaxy, however, the gravity of the galaxy deflects quasar light like a lens [ http://vela.astro.ulg.ac.be/themes/extragal/gravlens/bibdat/engl/index.html ], creating four bright images [ http://antwrp.gsfc.nasa.gov/apod/ap951220.html ] of the same distant quasar. When these images are all digitally subtracted, a distorted image of the background galaxy that hosts the quasar appears - here shown on the right in ghostly white. Each quasar [ http://www.student.nada.kth.se/~f93-cal/Qcontents.html ] image traces how the quasar looked at different times in the past, with the time between images influenced by the expansion rate [ http://antwrp.gsfc.nasa.gov/apod/ap960513.html ] of the universe itself. Assuming dark matter in the elliptical lens [ http://antwrp.gsfc.nasa.gov/apod/ap980111.html ] galaxy traces the visible matter, this expansion rate [ http://antwrp.gsfc.nasa.gov/debate/debate96.html ] can be characterized by a Hubble constant [ http://csep1.phy.ornl.gov/guidry/violence/hubble_constant.html ] of Ho near 65 km/sec/Mpc, a value close to that determined by other methods [ http://antwrp.gsfc.nasa.gov/apod/ap960110.html ]. Analysis [ http://xxx.lanl.gov/abs/astro-ph/9803207 ] of this image [ http://oposite.stsci.edu/pubinfo/pr/1998/37/ab.html ] by itself sheds little light on whether the global geometry of the universe [ http://antwrp.gsfc.nasa.gov/apod/ap980302.html ] is affected by a cosmological constant [ http://super.colorado.edu/~michaele/lambda.html ]. |
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Composite Crab
| Title |
Composite Crab |
| Explanation |
The Crab Pulsar, a city-sized, magnetized neutron star [ http://antwrp.gsfc.nasa.gov/apod/ap030201.html ] spinning 30 times a second, lies at the center of this composite image of the inner region of the well-known Crab Nebula [ http://www.seds.org/messier/m/m001.html ]. The spectacular picture combines optical data (red) from the Hubble Space Telescope [ http://hubblesite.org/gallery/ ] and x-ray images (blue) from the Chandra Observatory [ http://chandra.harvard.edu/fifth/ ], also used in the popular Crab Pulsar movies [ http://chandra.harvard.edu/photo/2002/0052/movies.html ]. Like a cosmic dynamo [ http://chandra.harvard.edu/chronicle/0201/vela.html ] the pulsar powers [ http://antwrp.gsfc.nasa.gov/apod/ap010602.html ] the x-ray and optical emission from the nebula, accelerating charged particles and producing the eerie, glowing x-ray jets. Ring-like structures are x-ray emitting regions where the high energy particles slam into the nebular material. The innermost ring is about a light-year across. With more mass than the Sun [ http://www.sunblock99.org.uk/sb99/fact/heavy.html ] and the density of an atomic nucleus [ http://hyperphysics.phy-astr.gsu.edu/hbase/ nuclear/nucuni.html#c2 ], the spinning pulsar is the collapsed core of a massive star that exploded, while the nebula is the expanding remnant of the star's outer layers. The supernova explosion was witnessed in the year 1054 [ http://www.seds.org/messier/more/m001_sn.html ]. |
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A Gallery of Gravitational M
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| Title |
A Gallery of Gravitational Mirages |
| Explanation |
The deeper you peer into the universe, the harder it is to see straight. The reason is that distant galaxies act as gravitational lenses [ http://vela.astro.ulg.ac.be/themes/extragal/gravlens/bibdat/engl/index.html ], deflecting light that passes nearby. These deflections result in the distortion of background sources [ http://antwrp.gsfc.nasa.gov/apod/ap980614.html ], and in some cases the creation of multiple images [ http://antwrp.gsfc.nasa.gov/apod/ap990331.html ]. Pictured above [ http://oposite.stsci.edu/pubinfo/pr/1999/18/index.html ], candidate artifacts of gravitational lensing [ http://imagine.gsfc.nasa.gov/docs/features/news/grav_lens.html ] have been found [ http://xxx.lanl.gov/abs/astro-ph/9902100 ] in images from the Medium Deep Survey [ http://archive.stsci.edu/mds/index.html ] being done with the Hubble Space Telescope [ http://www.stsci.edu/hst/ ]. Background source images that are lensed [ http://science.nasa.gov/newhome/headlines/ast14may99_1.htm ] by foreground galaxies include quasars, appearing as multiple blue smudges [ http://antwrp.gsfc.nasa.gov/apod/ap951220.html ], and galaxies, distorted into curving arcs [ http://antwrp.gsfc.nasa.gov/apod/ap981223.html ]. Unusual and interesting candidates [ http://oposite.stsci.edu/pubinfo/pr/1999/18/extra-photos.html ] for gravitational lensing include an edge-on galaxy disk [ http://antwrp.gsfc.nasa.gov/apod/ap981220.html ] which might be acting as a lens (upper left) and an image nicknamed London Underground [ http://www.jle.lul.co.uk/ ] (far left) which could well be the distortion of a background galaxy into an optical Einstein ring [ http://antwrp.gsfc.nasa.gov/apod/ap981102.html ]. |
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