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The Universe's First Firewor
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| Title |
The Universe's First Fireworks |
| Description |
The right panel is an image from NASA's Spitzer Space Telescope of stars and galaxies in the Ursa Major constellation. This infrared image covers a region of space so large that light would take up to 100 million years to travel across it. The left panel is the same image after stars, galaxies and other sources were masked out. The remaining background light is from a period of time when the universe was less than one billion years old, and most likely originated from the universe's very first groups of objects -- either huge stars or voracious black holes. Darker shades in the image on the left correspond to dimmer parts of the background glow, while yellow and white show the brightest light. |
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The Universe's First Firewor
…
| Title |
The Universe's First Fireworks |
| Description |
The right panel is an image from NASA's Spitzer Space Telescope of stars and galaxies in the Ursa Major constellation. This infrared image covers a region of space so large that light would take up to 100 million years to travel across it. The left panel is the same image after stars, galaxies and other sources were masked out. The remaining background light is from a period of time when the universe was less than one billion years old, and most likely originated from the universe's very first groups of objects -- either huge stars or voracious black holes. Darker shades in the image on the left correspond to dimmer parts of the background glow, while yellow and white show the brightest light. |
|
The Universe's First Firewor
…
| Title |
The Universe's First Fireworks |
| Description |
The right panel is an image from NASA's Spitzer Space Telescope of stars and galaxies in the Ursa Major constellation. This infrared image covers a region of space so large that light would take up to 100 million years to travel across it. The left panel is the same image after stars, galaxies and other sources were masked out. The remaining background light is from a period of time when the universe was less than one billion years old, and most likely originated from the universe's very first groups of objects -- either huge stars or voracious black holes. Darker shades in the image on the left correspond to dimmer parts of the background glow, while yellow and white show the brightest light. |
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Brief History of the Univers
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| Title |
Brief History of the Universe |
| Description |
This artist's timeline chronicles the history of the universe, from its explosive beginning to its mature, present-day state. Our universe began in a tremendous explosion known as the Big Bang about 13.7 billion years ago (left side of strip). Observations by NASA's Cosmic Background Explorer and Wilkinson Anisotropy Microwave Probe revealed microwave light from this very early epoch, about 400,000 years after the Big Bang, providing strong evidence that our universe did blast into existence. Results from the Cosmic Background Explorer were honored with the 2006 Nobel Prize for Physics. A period of darkness ensued, until about a few hundred million years later, when the first objects flooded the universe with light. This first light is believed to have been captured in data from NASA's Spitzer Space Telescope. The light detected by Spitzer would have originated as visible and ultraviolet light, then stretched, or redshifted, to lower-energy infrared wavelengths during its long voyage to reach us across expanding space. The light detected by the Cosmic Background Explorer and the Wilkinson Anisotropy Microwave Probe from our very young universe traveled farther to reach us, and stretched to even lower-energy microwave wavelengths. Astronomers do not know if the very first objects were either stars or quasars. The first stars, called Population III stars (our star is a Population I star), were much bigger and brighter than any in our nearby universe, with masses about 1,000 times that of our sun. These stars first grouped together into mini-galaxies. By about a few billion years after the Big Bang, the mini-galaxies had merged to form mature galaxies, including spiral galaxies like our own Milky Way. The first quasars ultimately became the centers of powerful galaxies that are more common in the distant universe. NASA's Hubble Space Telescope has captured stunning pictures of earlier galaxies, as far back as ten billion light-years away. |
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Far-Flung Supernovae Shed Li
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| Title |
Far-Flung Supernovae Shed Light on Dark Universe |
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Far-Flung Supernovae Shed Li
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| Title |
Far-Flung Supernovae Shed Light on Dark Universe |
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Far-Flung Supernovae Shed Li
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| Title |
Far-Flung Supernovae Shed Light on Dark Universe |
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The Secret Lives of Galaxies
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| Title |
The Secret Lives of Galaxies Unveiled in Deep Survey |
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The Secret Lives of Galaxies
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| Title |
The Secret Lives of Galaxies Unveiled in Deep Survey |
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The Secret Lives of Galaxies
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| Title |
The Secret Lives of Galaxies Unveiled in Deep Survey |
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Far-Flung Supernovae Shed Li
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| Title |
Far-Flung Supernovae Shed Light on Dark Universe |
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Far-Flung Supernovae Shed Li
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| Title |
Far-Flung Supernovae Shed Light on Dark Universe |
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Far-Flung Supernovae Shed Li
…
| Title |
Far-Flung Supernovae Shed Light on Dark Universe |
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The Secret Lives of Galaxies
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| Title |
The Secret Lives of Galaxies Unveiled in Deep Survey |
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The Secret Lives of Galaxies
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| Title |
The Secret Lives of Galaxies Unveiled in Deep Survey |
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The Secret Lives of Galaxies
…
| Title |
The Secret Lives of Galaxies Unveiled in Deep Survey |
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The Secret Lives of Galaxies
…
| Title |
The Secret Lives of Galaxies Unveiled in Deep Survey |
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The Secret Lives of Galaxies
…
| Title |
The Secret Lives of Galaxies Unveiled in Deep Survey |
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The Secret Lives of Galaxies
…
| Title |
The Secret Lives of Galaxies Unveiled in Deep Survey |
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The Secret Lives of Galaxies
…
| Title |
The Secret Lives of Galaxies Unveiled in Deep Survey |
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The Secret Lives of Galaxies
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| Title |
The Secret Lives of Galaxies Unveiled in Deep Survey |
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The Secret Lives of Galaxies
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| Title |
The Secret Lives of Galaxies Unveiled in Deep Survey |
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Hubble's Largest Galaxy Port
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| Title |
Hubble's Largest Galaxy Portrait Offers a New High-Definition View |
| General Information |
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. Giant galaxies weren?t assembled in a day. Neither was this Hubble Space Telescope image of the face-on spiral galaxy Messier 101 (M101). It is the largest and most detailed photo of a spiral galaxy that has ever been released from Hubble. The galaxy?s portrait is actually composed of 51 individual exposures taken with Hubble's Advanced Camera for Surveys and the Wide Field and Planetary Camera 2 in March 1994, September 1994, June 1999, November 2002, and January 2003. The newly composed image also includes elements from images from ground-based photos. |
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Hubble's Largest Galaxy Port
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| Title |
Hubble's Largest Galaxy Portrait Offers a New High-Definition View |
| General Information |
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. Giant galaxies weren?t assembled in a day. Neither was this Hubble Space Telescope image of the face-on spiral galaxy Messier 101 (M101). It is the largest and most detailed photo of a spiral galaxy that has ever been released from Hubble. The galaxy?s portrait is actually composed of 51 individual exposures taken with Hubble's Advanced Camera for Surveys and the Wide Field and Planetary Camera 2 in March 1994, September 1994, June 1999, November 2002, and January 2003. The newly composed image also includes elements from images from ground-based photos. |
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Hubble Finds that "Blue Blob
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| Title |
Hubble Finds that "Blue Blobs" in Space Are Orphaned Clusters of Stars |
| General Information |
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. What is an American Astronomical Society Meeting release? A major news announcement issued at an American Astronomical Society meeting, the premier astronomy conference. Hubble Space Telescope's powerful vision has resolved strange objects nicknamed "blue blobs" and found them to be brilliant blue clusters of stars born in the swirls and eddies of a galactic smashup 200 million years ago. Such "blue blobs"—, weighing tens of thousands of solar masses —, have never been seen in detail before in such sparse locations, say researchers. The "blue blobs" are found along a wispy bridge of gas strung among three colliding galaxies, M81, M82, and NGC 3077, residing about 12 million light-years away from Earth. This is not the place astronomers expect to find star clusters, because the gas filaments were considered too thin to accumulate enough material to actually build these many stars. The star clusters in this diffuse structure might have formed from gas collisions and subsequent turbulence, which enhanced locally the density of the gas streams. Galaxy collisions were much more frequent in the early universe, so "blue blobs" should have been common. After the stars burned out or exploded, the heavier elements forged in their nuclear furnaces would have been ejected to enrich intergalactic space. Read more: * The Full Story [ http://hubblesite.org/newscenter/archive/releases/2008/02/full/ ] |
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Hubble Finds that "Blue Blob
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| Title |
Hubble Finds that "Blue Blobs" in Space Are Orphaned Clusters of Stars |
| General Information |
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. What is an American Astronomical Society Meeting release? A major news announcement issued at an American Astronomical Society meeting, the premier astronomy conference. Hubble Space Telescope's powerful vision has resolved strange objects nicknamed "blue blobs" and found them to be brilliant blue clusters of stars born in the swirls and eddies of a galactic smashup 200 million years ago. Such "blue blobs"—, weighing tens of thousands of solar masses —, have never been seen in detail before in such sparse locations, say researchers. The "blue blobs" are found along a wispy bridge of gas strung among three colliding galaxies, M81, M82, and NGC 3077, residing about 12 million light-years away from Earth. This is not the place astronomers expect to find star clusters, because the gas filaments were considered too thin to accumulate enough material to actually build these many stars. The star clusters in this diffuse structure might have formed from gas collisions and subsequent turbulence, which enhanced locally the density of the gas streams. Galaxy collisions were much more frequent in the early universe, so "blue blobs" should have been common. After the stars burned out or exploded, the heavier elements forged in their nuclear furnaces would have been ejected to enrich intergalactic space. Read more: * The Full Story [ http://hubblesite.org/newscenter/archive/releases/2008/02/full/ ] |
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Hubble Finds that "Blue Blob
…
| Title |
Hubble Finds that "Blue Blobs" in Space Are Orphaned Clusters of Stars |
| General Information |
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. What is an American Astronomical Society Meeting release? A major news announcement issued at an American Astronomical Society meeting, the premier astronomy conference. Hubble Space Telescope's powerful vision has resolved strange objects nicknamed "blue blobs" and found them to be brilliant blue clusters of stars born in the swirls and eddies of a galactic smashup 200 million years ago. Such "blue blobs"—, weighing tens of thousands of solar masses —, have never been seen in detail before in such sparse locations, say researchers. The "blue blobs" are found along a wispy bridge of gas strung among three colliding galaxies, M81, M82, and NGC 3077, residing about 12 million light-years away from Earth. This is not the place astronomers expect to find star clusters, because the gas filaments were considered too thin to accumulate enough material to actually build these many stars. The star clusters in this diffuse structure might have formed from gas collisions and subsequent turbulence, which enhanced locally the density of the gas streams. Galaxy collisions were much more frequent in the early universe, so "blue blobs" should have been common. After the stars burned out or exploded, the heavier elements forged in their nuclear furnaces would have been ejected to enrich intergalactic space. Read more: * The Full Story [ http://hubblesite.org/newscenter/archive/releases/2008/02/full/ ] |
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Hubble Finds that "Blue Blob
…
| Title |
Hubble Finds that "Blue Blobs" in Space Are Orphaned Clusters of Stars |
| General Information |
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. What is an American Astronomical Society Meeting release? A major news announcement issued at an American Astronomical Society meeting, the premier astronomy conference. Hubble Space Telescope's powerful vision has resolved strange objects nicknamed "blue blobs" and found them to be brilliant blue clusters of stars born in the swirls and eddies of a galactic smashup 200 million years ago. Such "blue blobs"—, weighing tens of thousands of solar masses —, have never been seen in detail before in such sparse locations, say researchers. The "blue blobs" are found along a wispy bridge of gas strung among three colliding galaxies, M81, M82, and NGC 3077, residing about 12 million light-years away from Earth. This is not the place astronomers expect to find star clusters, because the gas filaments were considered too thin to accumulate enough material to actually build these many stars. The star clusters in this diffuse structure might have formed from gas collisions and subsequent turbulence, which enhanced locally the density of the gas streams. Galaxy collisions were much more frequent in the early universe, so "blue blobs" should have been common. After the stars burned out or exploded, the heavier elements forged in their nuclear furnaces would have been ejected to enrich intergalactic space. Read more: * The Full Story [ http://hubblesite.org/newscenter/archive/releases/2008/02/full/ ] |
|
Hubble Finds that "Blue Blob
…
| Title |
Hubble Finds that "Blue Blobs" in Space Are Orphaned Clusters of Stars |
| General Information |
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. What is an American Astronomical Society Meeting release? A major news announcement issued at an American Astronomical Society meeting, the premier astronomy conference. Hubble Space Telescope's powerful vision has resolved strange objects nicknamed "blue blobs" and found them to be brilliant blue clusters of stars born in the swirls and eddies of a galactic smashup 200 million years ago. Such "blue blobs"—, weighing tens of thousands of solar masses —, have never been seen in detail before in such sparse locations, say researchers. The "blue blobs" are found along a wispy bridge of gas strung among three colliding galaxies, M81, M82, and NGC 3077, residing about 12 million light-years away from Earth. This is not the place astronomers expect to find star clusters, because the gas filaments were considered too thin to accumulate enough material to actually build these many stars. The star clusters in this diffuse structure might have formed from gas collisions and subsequent turbulence, which enhanced locally the density of the gas streams. Galaxy collisions were much more frequent in the early universe, so "blue blobs" should have been common. After the stars burned out or exploded, the heavier elements forged in their nuclear furnaces would have been ejected to enrich intergalactic space. Read more: * The Full Story [ http://hubblesite.org/newscenter/archive/releases/2008/02/full/ ] |
|
Hubble Finds that "Blue Blob
…
| Title |
Hubble Finds that "Blue Blobs" in Space Are Orphaned Clusters of Stars |
| General Information |
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. What is an American Astronomical Society Meeting release? A major news announcement issued at an American Astronomical Society meeting, the premier astronomy conference. Hubble Space Telescope's powerful vision has resolved strange objects nicknamed "blue blobs" and found them to be brilliant blue clusters of stars born in the swirls and eddies of a galactic smashup 200 million years ago. Such "blue blobs"—, weighing tens of thousands of solar masses —, have never been seen in detail before in such sparse locations, say researchers. The "blue blobs" are found along a wispy bridge of gas strung among three colliding galaxies, M81, M82, and NGC 3077, residing about 12 million light-years away from Earth. This is not the place astronomers expect to find star clusters, because the gas filaments were considered too thin to accumulate enough material to actually build these many stars. The star clusters in this diffuse structure might have formed from gas collisions and subsequent turbulence, which enhanced locally the density of the gas streams. Galaxy collisions were much more frequent in the early universe, so "blue blobs" should have been common. After the stars burned out or exploded, the heavier elements forged in their nuclear furnaces would have been ejected to enrich intergalactic space. Read more: * The Full Story [ http://hubblesite.org/newscenter/archive/releases/2008/02/full/ ] |
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Messier 101
| Title |
Messier 101 |
| Explanation |
Big, beautiful spiral galaxy M101 is one of the last entries in Charles Messier's [ http://antwrp.gsfc.nasa.gov/apod/ap000311.html ] famous catalog, but definitely not one [ http://www.seds.org/messier/m/m102d.html ] of the least. About 170,000 light-years across, this galaxy is enormous, almost twice the size of our own Milky Way galaxy. M101 was also one of the original spiral nebulae [ http://www.seds.org/messier/more/m101_rosse.html ] observed by Lord Rosse's large 19th century telescope, the Leviathan [ http://www.birrcastle.com/telescopeHistory.htm ] of Parsontown. Assembled from 51 exposures recorded by the Hubble Space Telescope in the 20th and 21st centuries, with additional data from ground based telescopes, this mosaic of M101 [ http://hubblesite.org/newscenter/newsdesk/archive/ releases/2006/10/ ] is touted as the largest, most detailed spiral galaxy [ http://heritage.stsci.edu/2006/10/index.html ] view ever released from Hubble. The sharp image [ http://hubblesite.org/newscenter/newsdesk/archive/ releases/2006/10/fastfacts/ ] shows stunning features [ http://hubblesite.org/newscenter/newsdesk/archive/ releases/2006/10/image/a+zoom ] along the galaxy's face-on disk of stars and dust along with background galaxies, some visible right through M101 itself. Also known as the Pinwheel Galaxy, M101 [ http://www.seds.org/messier/m/m101.html ] lies within the boundaries of the northern constellation Ursa Major [ http://en.wikipedia.org/wiki/Ursa_Major ], about 25 million light-years away. |
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The Big Dipper Cluster
| Title |
The Big Dipper Cluster |
| Explanation |
A well-known asterism [ http://www.seds.org/Maps/Const/asterism.html ] in northern skies, The Big Dipper [ http://antwrp.gsfc.nasa.gov/apod/ap050218.html ] is easy to recognize even when viewed [ http://ncarboni.home.att.net/Astrophotography.html ] upside down. Part of the larger constellation of Ursa Major [ http://www.allthesky.de/various/umaumi.html ], the bright dipper stars [ http://spaceflight.nasa.gov/gallery/images/station/crew-6/ html/iss006e40544.html ] above are named [ http://www.astro.uiuc.edu/~kaler/sow/uma-bd-t.html ] (left to right along the dipper) Dubhe, Merak, Phecda, Megrez, Alioth, Mizar/Alcor, and Alkaid. Of course [ http://www.astropix.com/HTML/C_SPRING/URSAS.HTM ], stars in any given constellation [ http://www.astro.wisc.edu/~dolan/constellations/ extra/constellations.html ] are unlikely to be physically related [ http://www.comfychair.org/~cmbell/myth/myth.html ]. But surprisingly, most of the big dipper stars do seem to be headed in the same direction as they plough [ http://www.dibonsmith.com/uma_con.htm ] through space, a property they share with other stars spread out over an even larger area across the sky. Their measured common motion [ http://www.kencroswell.com/DescendantsOfTheDipper.html ] suggests that they all belong to a loose, nearby star cluster [ http://antwrp.gsfc.nasa.gov/apod/ap051118.html ], thought to be on average only about 75 light-years away and up to 30 light-years across. The cluster is more properly known as the Ursa Major Moving Group [ http://en.wikipedia.org/wiki/Ursa_Major_moving_group ]. |
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Smoke from the Cigar Galaxy
| Title |
Smoke from the Cigar Galaxy |
| Explanation |
Very bright in infrared light [ http://coolcosmos.ipac.caltech.edu/image_galleries/ ir_yellowstone/ ], well-known starburst galaxy M82's popular name describes its suggestive shape seen at visible [ http://antwrp.gsfc.nasa.gov/apod/ap961118.html ] wavelengths - The Cigar Galaxy [ http://www.seds.org/messier/m/m082.html ]. Ironically, M82's fantastic appearance in this Spitzer Space Telescope image [ http://www.spitzer.caltech.edu/Media/releases/ ssc2006-09/release.shtml ] really is due to cosmic "smoke" - the infrared emission of exented dust features blown by stellar winds from M82's luminous, central star forming regions. The false-color view highlights a component of dust emission from complex carbon molecules called polycyclic aromatic hydrocarbons [ http://www.seds.org/messier/m/m082.html ] or PAHs. PAHs are also seen in star forming regions throughout our own, much calmer, Milky Way Galaxy and are products of combustion on planet Earth [ http://web99.arc.nasa.gov/~astrochm/ PAHs.html ]. Likely triggered by interactions with nearby galaxy M81, M82's intense [ http://antwrp.gsfc.nasa.gov/apod/ap041230.html ] star formation activity appears to be blowing out immense clouds of dust and PAHs extending nearly 20,000 light-years both above and below the galactic plane. M82 is [ http://www.robgendlerastropics.com/M82text.html ] about 12 million light-years away in the constellation Ursa Major. |
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M82: Galaxy with a Supergala
…
| Title |
M82: Galaxy with a Supergalactic Wind |
| Explanation |
What's lighting up the Cigar Galaxy? M82 [ http://www.seds.org/messier/m/m082.html ], as this irregular galaxy [ http://www.seds.org/messier/irre.html ] is also known, was stirred up by a recent pass [ http://antwrp.gsfc.nasa.gov/apod/ap060415.html ] near large spiral [ http://antwrp.gsfc.nasa.gov/apod/spiral_galaxies.html ] galaxy M81 [ http://antwrp.gsfc.nasa.gov/apod/ap020620.html ]. This doesn't fully explain the source of the red-glowing outwardly expanding gas, however. Recent evidence [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1999ApJ...523..575L ] indicates that this gas is being driven out by the combined emerging particle winds [ http://www-spof.gsfc.nasa.gov/Education/wsolwind.html ] of many stars, together creating a galactic "superwind." The above photographic mosaic [ http://hubblesite.org/newscenter/newsdesk/archive/releases/2006/14/image/a ], released yesterday to commemorate the sixteenth anniversary [ http://hubblesite.org/newscenter/newsdesk/archive/releases/2006/14/ ] of the Hubble Space Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap010806.html ], highlights a specific color of red light strongly emitted by ionized hydrogen [ http://en.wikipedia.org/wiki/Hydrogen ] gas, showing detailed filaments of this gas. The filaments extend for over 10,000 light year [ http://www.howstuffworks.com/question94.htm ]s. The 12-million light-year distant Cigar Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap040601.html ] is the brightest galaxy in the sky in infrared [ http://coolcosmos.ipac.caltech.edu/cosmic_classroom/ir_tutorial/ ] light, and can be seen in visible light with a small telescope [ http://www.howstuffworks.com/telescope.htm ] towards the constellation [ http://www.astro.wisc.edu/~dolan/constellations/extra/constellations.html ] of Ursa Major [ http://www.astronomical.org/portal/modules/wfsection/article.php?articleid=83 ]. |
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A Superwind from the Cigar G
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| Title |
A Superwind from the Cigar Galaxy |
| Explanation |
What's lighting up the Cigar Galaxy? M82 [ http://www.seds.org/messier/m/m082.html ], as this irregular galaxy [ http://www.seds.org/messier/irre.html ] is also known, was stirred up by a recent pass [ http://antwrp.gsfc.nasa.gov/apod/ap000209.html ] near large spiral [ http://antwrp.gsfc.nasa.gov/apod/spiral_galaxies.html ] galaxy M81 [ http://antwrp.gsfc.nasa.gov/apod/ap970726.html ]. This doesn't fully explain the source of the red-glowing outwardly expanding gas, however. Recent evidence [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1999ApJ...523..575L ] indicates that this gas is being driven out by the combined emerging particle winds [ http://www-spof.gsfc.nasa.gov/Education/wsolwind.html ] of many stars, together creating a galactic "superwind." The above recently released photograph [ http://www.subaru.naoj.org/Science/press_release/0003/M82.html ] from the new Subaru Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap990201.html ] highlights the specific color of red light [ http://csep10.phys.utk.edu/astr162/lect/light/absorption.html ] strongly emitted by ionized hydrogen [ http://pearl1.lanl.gov/periodic/elements/1.html ] gas, showing detailed filaments of this gas. The filaments extend for over 10,000 light year [ http://www.howstuffworks.com/question94.htm ]s. The 12-million light-year distant Cigar Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap980315.html ] is the brightest galaxy in the sky in infrared [ http://www.eecs.umich.edu/mathscience/funexperiments/agesubject/lessons/newton/infrared.html ] light, and can be seen in visible light with a small telescope towards the constellation [ http://www.astro.wisc.edu/~dolan/constellations/extra/constellations.html ] of Ursa Major [ http://www.astronomical.org/constellations/uma.html ]. |
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Bright Galaxy M81
| Title |
Bright Galaxy M81 |
| Explanation |
Big and beautiful spiral galaxy M81 [ http://www.seds.org/messier/m/m081.html ] lies in the northern constellation Ursa Major [ http://www.dibonsmith.com/uma_con.htm ]. One of the brightest galaxies in planet Earth's sky, M81 is also home to the second brightest supernova seen [ http://antwrp.gsfc.nasa.gov/apod/ap050910.html ] in modern times. This superbly detailed view [ http://www.astrogb.com/m81.htm ] reveals M81's bright yellow nucleus, blue spiral arms, and sweeping cosmic dust lanes with a scale comparable to the Milky Way [ http://cassfos02.ucsd.edu/public/tutorial/MW.html ]. Hinting at a disorderly past, a remarkable dust lane actually runs straight through the disk, below and right of the galactic center, contrary to M81's other [ http://www.astr.ua.edu/gifimages/m81series2.html ] prominent spiral [ http://burro.astr.cwru.edu/Academics/Astr222/Galaxies/Spiral/ spiral.html ] features. The errant dust lane [ http://antwrp.gsfc.nasa.gov/apod/ap010112.html ] may be the lingering result of a close encounter [ http://antwrp.gsfc.nasa.gov/apod/ap060415.html ] between M81 and its smaller companion galaxy, M82 [ http://antwrp.gsfc.nasa.gov/apod/ap060425.html ]. Scrutiny of variable stars in M81 (aka NGC 3031) has yielded one of the best determined distances [ http://www.ipac.caltech.edu/H0kp/m81/m81.html ] for an external galaxy -- 11.8 million light-years. |
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M101: An Ultraviolet View
| Title |
M101: An Ultraviolet View |
| Explanation |
This picture of giant spiral galaxy Messier 101 (M101) [ http://www.seds.org/messier/m/m101.html ] was taken by the Ultraviolet Imaging Telescope [ http://hypatia.gsfc.nasa.gov/astro/uit/uit.html ] (UIT). UIT [ http://hypatia.gsfc.nasa.gov/astro/uit/uitcutaway.html ] flew into orbit as part of the Astro 2 mission [ http://www.ksc.nasa.gov/shuttle/missions/sts-67/mission-sts-67.html ] on-board the Space Shuttle Endeavour in March 1995. The image has been processed [ http://trifle.gsfc.nasa.gov/UIT/Astro2/Astro2_pictures.html ] so that the colors (dark purple through white) represent an increasing intensity of ultraviolet light [ http://imagine.gsfc.nasa.gov/docs/introduction/ emspectrum.html ]. Pictures of galaxies like this one show mainly clouds of gas containing newly formed stars many times more massive than the sun, which glow strongly in the ultraviolet. In contrast, visible light pictures of galaxies [ http://www.seds.org/messier/more/m101_more.html ] tend to be dominated by the yellow and red light of older stars. Ultraviolet light [ http://titan.srrb.noaa.gov/UV/ ], invisible to the human eye, is blocked by ozone in the atmosphere [ http://jwocky.gsfc.nasa.gov/ ] so ultraviolet pictures of celestial objects must be taken from space. M101 is a mere 22 million light-years away in the constellation Ursa Major [ http://www.seds.org/Maps/Stars_en/Fig/ursamajor.html ]. Its popular moniker is the Pinwheel Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap970805.html ]. |
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Extra Galaxies
| Title |
Extra Galaxies |
| Explanation |
Careful inspection of the full field of view for this sharp composite [ http://www.caelumobservatory.com/gallery/sky.shtml ] image reveals a surprising number of galaxies both near and far toward the constellation Ursa Major [ http://www.allthesky.com/constellations/ursamajor/ ]. The most striking is clearly NGC 3718 [ http://www.kopernik.org/images/archive/n3718.htm ], a warped spiral galaxy found near picture center. NGC 3718's faint spiral arms look twisted and extended [ http://antwrp.gsfc.nasa.gov/apod/ap060108.html ], its bright central region crossed by obscuring dust lanes. A mere 150 thousand light-years to the right is another [ http://panther-observatory.com/gallery/deepsky/ doc/NGC3718_cass.htm ] large spiral galaxy, NGC 3729. The two are likely interacting [ http://www.npaci.edu/online/v4.9/galaxies2.html ] gravitationally, accounting for the peculiar [ http://antwrp.gsfc.nasa.gov/apod/ap051008.html ] appearance of NGC 3718. While this galaxy pair lies about 52 million light-years away, the remarkable Hickson [ http://nedwww.ipac.caltech.edu/level5/Sept01/ Hickson/Hickson_contents.html ] Group 56 can also be seen clustered just below NGC 3718. Hickson Group 56 [ http://www.kopernik.org/images/archive/hick56.htm ] consists of five interacting galaxies and lies over 400 million light-years away. |
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The Hubble Deep Field
| Title |
The Hubble Deep Field |
| Explanation |
Galaxies [ http://www.limber.org/HDF.html ] like colorful pieces of candy fill the Hubble Deep Field [ http://www.stsci.edu/pubinfo/press-releases/96-01.txt ] - one of humanity's most distant [ http://oposite.stsci.edu/pubinfo/background-text/hdf.txt ] optical views of the Universe [ http://www.stsci.edu/pubinfo/PR/96/01.html ]. The dimmest, some as faint as 30th magnitude (about four billion times fainter than stars visible to the unaided eye), are very distant galaxies [ http://antwrp.gsfc.nasa.gov/apod/ap960628.html ] and represent what the Universe [ http://antwrp.gsfc.nasa.gov/apod/ap990905.html ] looked like in the extreme past, perhaps less than one billion years after the Big Bang [ http://csep1.phy.ornl.gov/guidry/violence/cosmology.html ]. To make the Deep Field image [ http://www.stsci.edu/ftp/observer/hdf/references/ferguson_aas.html ], astronomers selected an uncluttered area of the sky [ http://www.stsci.edu/ftp/observer/hdf/project/field.html ] in the constellation Ursa Major [ http://antwrp.gsfc.nasa.gov/apod/ap000709.html http://www.seds.org/Maps/Stars_en/Fig/ursamajor.html ] (the Big Bear) and pointed the Hubble Space Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap950810.html ] at a single spot for 10 days accumulating and combining many separate exposures. With each additional exposure [ http://antwrp.gsfc.nasa.gov/apod/ap981214.html ], fainter objects were revealed. The final result can be used to explore [ http://www.stsci.edu/pubinfo/PR/97/hdf-key-findings.html ] the mysteries of galaxy evolution [ http://www.journals.uchicago.edu/ApJ/journal/ issues/ApJL/v473n1/5169/5169.html ] and the infant Universe [ http://antwrp.gsfc.nasa.gov/apod/ap980302.html ]. |
|
Tails Of Comet LINEAR
| Title |
Tails Of Comet LINEAR |
| Explanation |
Comet C/1999 S4 LINEAR is only one of many [ http://www.ll.mit.edu/LINEAR/neos.html ] comets discovered with the Lincoln Near Earth Asteroid Research [ http://www.ll.mit.edu/LINEAR/ ] (LINEAR) telescope operating near Soccoro, New Mexico, USA. Traveling steadily southward through Earth's night sky, C/1999 S4 passed perihelion (closest approach to the Sun) yesterday on what is likely its first trip [ http://www.skypub.com/sights/comets/0007linearS4.html ] through the inner solar system. Now fading, comet LINEAR [ http://www.swisr.org/newcomet.html#Anchor Latest ] became no brighter than about 6th magnitude, but is still easily visible with binoculars in northern hemisphere skies. While the memorable comets Hale-Bopp [ http://antwrp.gsfc.nasa.gov/apod/ap970320.html ] and Hyakutake [ http://antwrp.gsfc.nasa.gov/apod/ap980717.html ] were much brighter, comet LINEAR [ http://antwrp.gsfc.nasa.gov/apod/ap000704.html ] is displaying [ http://cfa-www.harvard.edu/iauc/07400/07461.html#Item2 ] delightful tails evident in this false-color composite image from [ http://www.fiz.uni-lj.si/astro/comets/images/99s4.html ] the Crni Vrh Observatory [ http://www.fiz.uni-lj.si/astro/comets/cvobs.html ] in Slovenia. The combined series of exposures made on July 22nd are registered on the comet. In the resulting picture, stars appear as rows of dots, but the faint structures in the comet's tail are beautifully recorded. Presently seen moving from Ursa Major to Leo [ http://www.astro.wisc.edu/~dolan/constellations/ constellations.html ] this comet LINEAR [ http://encke.jpl.nasa.gov/whats_visible.html#1999S4 ] will begin to shine in southern hemisphere skies in August. |
|
Gangly Spiral Galaxy NGC 318
…
| Title |
Gangly Spiral Galaxy NGC 3184 |
| Explanation |
NGC 3184 is a large spiral galaxy [ http://www.seds.org/messier/spir.html ] with a small nucleus and long sprawling spiral arms. Although NGC 3184 [ http://www.kopernik.org/images/archive/n3184.htm ] contains hundreds of billions of stars, the blue color of its spiral arms [ http://online.bc.cc.ca.us/sea/astronomy/ismnotesb/ismglxyc.htm ] comes mostly from relatively few bright young blue stars [ http://antwrp.gsfc.nasa.gov/apod/ap000227.html ]. The galaxy is not empty of matter between these spiral [ http://antwrp.gsfc.nasa.gov/apod/spiral_galaxies.html ] arms -- the bright stars that highlight the arms were created in huge density waves [ http://fuse.pha.jhu.edu/~danforth/spiral/ ] that circle the center. Visible [ http://www.ghg.net/akelly/ ] with a small telescope towards the constellation [ http://www.att.virtualclassroom.org/vc99/vc_04/cons_stars/cons/hist_cons.html ] of Ursa Major [ http://www.astronomical.org/constellations/uma.html ], light takes about 25 million years to reach us from NGC 3184 [ http://home.cc.umanitoba.ca/~umgonza4/histobserv.html ], and about 50,000 years just to cross it. NGC 3184 [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1997A%26AS..124..129P ] (Hubble type [ http://www.seds.org/messier/xtra/supp/gal-ttab.html ] Sbc) is notable for its high abundance [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1982PhDT........35M ] of heavy elements [ http://casa.colorado.edu/~uvconf/white_final/node5.html ] and a supernova [ http://imagine.gsfc.nasa.gov/docs/science/know_l2/supernovae.html ] that has occurred there recently [ http://cfa-www.harvard.edu/iauc/07300/07329.html#Item1 ]. |
|
The Big Dipper
| Title |
The Big Dipper |
| Explanation |
Do you see it? This common question frequently precedes the rediscovery of one of the most commonly recognized configurations of stars on the northern sky: the Big Dipper [ http://en.wikipedia.org/wiki/Big_dipper ]. This grouping of stars is one of the few things that has likely been seen, and will be seen, by every generation. The Big Dipper is not by itself a constellation [ http://en.wikipedia.org/wiki/Constellation#History_of_the_constellations ]. Although part of the constellation of the Great Bear [ http://www.astro.wisc.edu/~dolan/constellations/constellations/Ursa_Major.html ] (Ursa Major), the Big Dipper [ http://antwrp.gsfc.nasa.gov/apod/ap050218.html ] is an asterism [ http://www.seds.org/Maps/Const/asterism.html ] that has been known by different names to different societies. Five of the Big Dipper stars [ http://www.newton.dep.anl.gov/askasci/ast99/ast99237.htm ] are actually near each other in space and were likely formed at nearly the same time. Connecting two stars in the far part of the Big Dipper will lead one to Polaris [ http://antwrp.gsfc.nasa.gov/apod/ap991006.html ], the North Star, which is part of the Little Dipper [ http://en.wikipedia.org/wiki/Little_Dipper ]. Relative stellar motions will cause the Big Dipper [ http://www.dustbunny.com/afk/constellations/bigdipper/ ] to slowly change its apparent configuration [ http://www.astropix.com/HTML/SHOW_DIG/038.HTM ] over the next 100,000 years. |
|
Polar Ring Galaxy NGC 2685
| Title |
Polar Ring Galaxy NGC 2685 |
| Explanation |
NGC 2685 is [ http://www.seds.org/~spider/Spider/Misc/n2685.html ] a confirmed polar ring galaxy - a rare type of galaxy [ http://www.seds.org/messier/galaxy.html ] with stars, gas and dust orbiting in rings perpendicular to the plane of a flat galactic disk. The bizarre [ http://antwrp.gsfc.nasa.gov/apod/ap990510.html ] configuration could be caused by the chance capture of material [ http://www.astro.spbu.ru/EducTech/prg.html ] from another galaxy by a disk galaxy, with the captured debris strung out in a rotating ring. Still, observed [ http://arxiv.org/abs/astro-ph0209004 ] properties of NGC 2685 suggest that the rotating ring structure is remarkably old and stable. In this fascinating [ http://www.rdelsol.com/Galaxy/NGC2685.html ] view of the peculiar system also known as Arp [ http://nedwww.ipac.caltech.edu/level5/Arp/frames.html ] 336 or the Helix galaxy, the strange, perpendicular rings [ http://www.obspm.fr/actual/nouvelle/ apr03/prg.en.shtml ] are easy to trace as they pass in front of the galactic disk, along with other disturbed outer structures. NGC 2685 is about 50,000 light-years across and 40 million light-years away in the constellation Ursa Major [ http://www.wikisky.org/?object=Ursa+Major&zoom=2 ]. |
|
Spiral Galaxy NGC 3310 in Ul
…
| Title |
Spiral Galaxy NGC 3310 in Ultraviolet |
| Explanation |
Why is NGC 3310 bursting with young stars? The brightest of these new stars are so hot that they light up this spiral galaxy not only in blue light, but in light so blue humans can't see it: ultraviolet [ http://snoopy.gsfc.nasa.gov/~orfeus2/ultraviolet.html ]. The Hubble Space Telescope [ http://www.stsci.edu/hst/ ] took the above photograph [ http://oposite.stsci.edu/pubinfo/PR/2001/04/index.html ] in different bands of ultraviolet light. Speculation holds that NGC 3310 [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1996ApJ...473L..21S ] collided with one of its own dwarf companion galaxies [ http://antwrp.gsfc.nasa.gov/apod/ap991003.html ] only about 50 million years previously. This merger sent density waves [ http://fuse.pha.jhu.edu/~danforth/spiral/ ] rippling around the spiral disk, causing many gas clouds to condense into star forming regions. Imaging nearby galaxies in ultraviolet light [ http://oposite.stsci.edu/pubinfo/PR/2001/04/fastfacts.html ] allows astronomers to better understand the images of distant highly redshift [ http://www.astro.virginia.edu/~jh8h/glossary/redshift.htm ]ed galaxies in visible light, and so to understand why many of these distant galaxies appear relatively fragmented [ http://antwrp.gsfc.nasa.gov/apod/ap000709.html ]. The unusually smooth NGC 3310 [ http://oposite.stsci.edu/pubinfo/PR/2001/04/content/prc0104.txt ] spans over 20 thousand light years [ http://www.howstuffworks.com/question94.htm ] and lies about 50 million light years away towards the constellation of Ursa Major [ http://www.astronomical.org/constellations/uma.html ]. |
|
M81 in Ursa Major
| Title |
M81 in Ursa Major |
| Explanation |
One of the brightest galaxies in planet Earth's sky and similar in size to the Milky Way [ http://www.atlasoftheuniverse.com/galaxy.html ], big, beautiful spiral M81 [ http://antwrp.gsfc.nasa.gov/apod/ap060707.html ] lies 11.8 million light-years away in the northern constellation Ursa Major. This remarkably deep image [ http://astrophoto.com/M81LRGBDEEP.htm ] of the region reveals details in the bright yellow core, but at the same time follows fainter features along the galaxy's gorgeous blue spiral arms and sweeping dust lanes. Above M81 lies a dwarf companion galaxy, Holmberg IX [ http://seds.org/MESSIER/more/m081_hom9.html ], sporting a large, pinkish star-forming [ http://antwrp.gsfc.nasa.gov/apod/ap061123.html ] region near the top. While M81 [ http://coolcosmos.ipac.caltech.edu//cosmic_classroom/ multiwavelength_astronomy/multiwavelength_museum/m81.html ] and Holmberg IX are seen through a foreground of stars in our own Milky Way galaxy, they are also seen here through a much fainter complex of dust clouds. The relatively unexplored clouds [ http://antwrp.gsfc.nasa.gov/apod/ap050929.html ] are likely only some hundreds of light-years distant and lie high above our galaxy's plane. Scattered through the image, especially at the the right, the dust clouds reflect the combined light of the Milky Way's stars and have been dubbed integrated flux nebulae [ http://www.galaxyimages.com/UNP_IFNebula.html ]. |
|
Bright Spiral Galaxy M81 in
…
| Title |
Bright Spiral Galaxy M81 in Ultraviolet from Galex |
| Explanation |
Where are the hot stars in M81, one of the closest major spiral galaxies? To help find out, astronomers took a deep image in ultraviolet light [ http://science.hq.nasa.gov/kids/imagers/ems/uv.html ] of the sprawling spiral with the Earth-orbiting Galex telescope [ http://www.galex.caltech.edu/TECHNOLOGY/technology.html ]. Hot stars emit more ultraviolet than cool stars, and are frequently associated with young open clusters [ http://antwrp.gsfc.nasa.gov/apod/ap060501.html ] of stars and energetic star forming regions [ http://antwrp.gsfc.nasa.gov/apod/ap070430.html ]. Magnificent spiral galaxy [ http://csep10.phys.utk.edu/astr162/lect/galaxies/spiral.html ] M81, slightly smaller in size to our own Milky Way Galaxy [ http://cassfos02.ucsd.edu/public/tutorial/MW.html ], shows off its young stars in its winding spiral arms in the above image [ http://www.nasa.gov/mission_pages/galex/image-galex-20070501.html ]. Less than 100 million years old, the young stars are blue in the above false-color Galex image [ http://www.nasa.gov/mission_pages/galex/image-galex-20070501.html ] and seen to be well separated from the older yellowish stars of the galactic core. Visible above M81 [ http://antwrp.gsfc.nasa.gov/apod/ap070427.html ] is a satellite galaxy dubbed Holmberg IX [ http://ftp.seds.org/Messier/more/m081_hom9.html ]. Studying the unexpectedly bright ultraviolet glow of this small irregular galaxy [ http://en.wikipedia.org/wiki/Irregular_galaxies ] may help astronomers understand how the many satellites [ http://www.astro.uu.se/~ns/mwsat.html ] of our own Milky Way Galaxy developed. M81 [ http://seds.lpl.arizona.edu/messier/m/m081.html ], visible through a small telescope, spans about 70,000 light years [ http://chandra.harvard.edu/photo/cosmic_distance.html ] and lies about 12 million light years away toward the constellation [ http://www.astro.wisc.edu/~dolan/constellations/extra/constellations.html ] of the Great Bear (Ursa Major [ http://www.astro.wisc.edu/~dolan/constellations/constellations/Ursa_Major.html ]). |
|
M82 After the Crash
| Title |
M82 After the Crash |
| Explanation |
When did the Cigar Galaxy light up? Evidence indicates "how" M82, the Cigar Galaxy [ http://apod.gsfc.nasa.gov/cgi-bin/apod/apod_search?M82 ], became so bright and peculiar: it collided [ http://antwrp.gsfc.nasa.gov/apod/ap000209.html ] with neighboring galaxy M81 [ http://www.seds.org/messier/m/m081.html ]. Astronomers become detectives, however, when trying to figure out "when" this collision occurred. Inspection of this [ http://oposite.stsci.edu/pubinfo/PR/2001/08/index.html ] and other Hubble Space Telescope [ http://www.stsci.edu/hst/ ] images now indicate massive young [ http://antwrp.gsfc.nasa.gov/apod/ap010311.html ] globular star clusters [ http://antwrp.gsfc.nasa.gov/apod/globular_clusters.html ] were formed during the encounter. Stars in these clusters that are 600 million years old are just now exhausting [ http://observe.ivv.nasa.gov/nasa/space/stellardeath/stellardeath_intro.html ] their central hydrogen [ http://antwrp.gsfc.nasa.gov/apod/ap010113.html ] fuel, indicating [ http://xxx.lanl.gov/abs/astro-ph/0010046 ] that the Cigar Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap000404.html ]'s brightening occurred just that long ago. M82 [ http://www.seds.org/messier/m/m082.html ] is located about 12 million light years [ http://www.treasure-troves.com/astro/Light-Year.html ] away and visible [ http://oposite.stsci.edu/pubinfo/PR/2001/08/fastfacts.html ] with binoculars [ http://www.skypub.com/tips/binoculars/halfway.html ] towards the constellation [ http://www.starshine.com/frankn/Constellations.asp ] of Ursa Major [ http://www.astro.wisc.edu/~dolan/constellations/constellations/Ursa_Major.html ]. The star-field shown above [ http://hubble.esa.int/hubble/news/index.cfm?aid=31&cid=630&oid=26349 ] spans about 10,000 light years. |
|
Bright Spiral Galaxy M81 fro
…
| Title |
Bright Spiral Galaxy M81 from Hubble |
| Explanation |
The Hubble Space Telescope has resolved individual stars in a spectacular new image of nearby spiral galaxy M81. The feat is similar to Edwin Hubble [ http://en.wikipedia.org/wiki/Edwin_Hubble ]'s historic images with the Mt. Wilson 100-inch Hooker Telescope [ http://en.wikipedia.org/wiki/Mount_Wilson_Observatory#100_inch_.282.5_m.29_Hooker_telescope ] in the 1920s that resolved stars [ http://antwrp.gsfc.nasa.gov/apod/ap960406.html ] in neighboring galaxy M31 [ http://antwrp.gsfc.nasa.gov/apod/ap061126.html ]. Edwin Hubble [ http://antwrp.gsfc.nasa.gov/apod/ap960217.html ] was able to use individual Cepheid variable stars [ http://antwrp.gsfc.nasa.gov/apod/ap960110.html ] to show that M31 was not nearby swirling gas but rather an entire galaxy [ http://antwrp.gsfc.nasa.gov/diamond_jubilee/debate20.html ] like our Milky Way Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap050825.html ]. This above image [ http://www.cfa.harvard.edu/press/2007/pr200716_images.html ] in visible light [ http://science.hq.nasa.gov/kids/imagers/ems/visible.html ] taken by the Hubble Space Telescope [ http://www.stsci.edu/hst/HST_overview/ ] is being used in conjunction with images [ http://antwrp.gsfc.nasa.gov/apod/ap070515.html ] being taken in ultraviolet [ http://science.hq.nasa.gov/kids/imagers/ems/uv.html ] by Galex [ http://en.wikipedia.org/wiki/GALEX ], infrared by Spitzer [ http://en.wikipedia.org/wiki/Spitzer_Space_Telescope ], and X-rays [ http://science.hq.nasa.gov/kids/imagers/ems/xrays.html ] with Chandra [ http://en.wikipedia.org/wiki/Chandra_X-ray_Observatory ] to study how stars have formed and died over the history M81. Light takes about 12 million years [ http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question19.html ] to reach us from M81. M81 [ http://seds.org/messier/m/m081.html ] is visible with binoculars toward the constellation of the Great Bear (Ursa Major [ http://www.astronomical.org/portal/modules/wfsection/article.php?articleid=83 ]). |
|
X-Ray Rainbows
| Title |
X-Ray Rainbows |
| Explanation |
A drop of water or prism of [ http://www.phys.virginia.edu/classes/620/ light_activities.html#Prism ] glass can spread out visible sunlight into a rainbow of colors [ http://www.unidata.ucar.edu/staff/blynds/rnbw.html ]. In order of increasing energy, the well known spectrum of colors in a rainbow [ http://www.kncsoftware.com/knc1/classroom/harry/rainbows/ rainbows.htm ] runs red, orange, yellow, green, blue, indigo, violet. X-ray light too [ http://chandra.harvard.edu/xray_astro/xrays.html ] can be spread out into a spectrum [ http://micro.magnet.fsu.edu/primer/java/scienceopticsu/ newton/index.html ] ordered by energy ... but not by drops of water or glass. Instead, the orbiting Chandra [ http://asc.harvard.edu/udocs/overview_cxo.html ] X-ray Observatory uses a set of 540 finely ruled, gold gratings to spread out the x-rays, recording the results with digital detectors. The resulting x-ray spectrum reveals much about the compositions, temperatures, and motions within cosmic x-ray sources [ http://imagine.gsfc.nasa.gov/docs/science/know_l2/ history_xray.html ]. This false color Chandra image shows [ http://chandra.harvard.edu/photo/cycle1/xtej1118/ index.html ] the x-ray spectrum of a star system in Ursa Major [ http://www.allthesky.com/constellations/ ursamajor/ ] cataloged as XTE J1118+480 and thought to consist of a sun-like star orbiting a black hole [ http://antwrp.gsfc.nasa.gov/apod/ap010119.html ]. Unlike the familiar appearance of a prism's visible light rainbow [ http://micro.magnet.fsu.edu/optics/activities/students/ prismsstudent.html ], the energies here are ordered along radial lines with the highest energy x-rays near the center and lowest energies near the upper left and lower right edges of the image. The central spiky region itself is created by x-rays from the source which are not spread out by the array of gratings. |
|
The Bubbling Cauldron of NGC
…
| Title |
The Bubbling Cauldron of NGC 3079 |
| Explanation |
Edge-on [ http://antwrp.gsfc.nasa.gov/apod/ap010510.html ] spiral galaxy NGC 3079 is a mere 50 million light-years away toward the constellation Ursa Major. Shown in this [ http://oposite.stsci.edu/pubinfo/PR/2001/28/ index.html ] stunning false-color Hubble Space Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap010806.html ] image, the galaxy's disk - composed of spectacular star clusters in winding spiral arms and dramatic dark lanes of dust - spans some [ http://heasarc.gsfc.nasa.gov/docs/cosmic/cosmic.html ] 70,000 light-years. Still, NGC 3079's [ http://oposite.stsci.edu/pubinfo/PR/2001/28/ fastfacts.html ] most eye-catching features are the pillars of gas which tower above a swirling cosmic cauldron of activity at the galaxy's center. Seen in the close-up inset at lower right, the pillars rise to a height of about 2,000 light-years and seem to lie on the surface of an immense bubble rising from the galactic core. Measurements indicate that the gaseous pillars are streaming away from the core at 6 million kilometers per hour. What makes [ http://oposite.stsci.edu/pubinfo/PR/2001/28/ faq.html ] this galaxy's cauldron bubble [ http://tech-two.mit.edu/Shakespeare/macbeth/ macbeth.4.1.html ]? Astronomers are exploring [ http://xxx.lanl.gov/abs/astro-ph/0101010 ] the possibility that the superbubble [ http://antwrp.gsfc.nasa.gov/apod/ap991130.html ] is formed by winds [ http://www.physics.unc.edu/~cecil/science.html ] from massive stars. If so, these massive stars were likely born all at once as the galactic center underwent a sudden burst [ http://antwrp.gsfc.nasa.gov/apod/ap010124.html ] of star formation. |
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