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Andromeda of Milky Way Galaxy and Washington, D.C.
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Dwarf Galaxies Swimming in T
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| Title |
Dwarf Galaxies Swimming in Tidal Tails |
| Description |
This false-color infrared image from NASA's Spitzer Space Telescope shows little "dwarf galaxies" forming in the "tails" of two larger galaxies that are colliding together. The big galaxies are at the center of the picture, while the dwarfs can be seen as red dots in the red streamers, or tidal tails. The two blue dots above the big galaxies are stars in the foreground. Galaxy mergers are common occurrences in the universe, for example, our own Milky Way galaxy will eventually smash into the nearby Andromeda galaxy. When two galaxies meet, they tend to rip each other apart, leaving a trail, called a tidal tail, of gas and dust in their wake. It is out of this galactic debris that new dwarf galaxies are born. The new Spitzer picture demonstrates that these particular dwarfs are actively forming stars. The red color indicates the presence of dust produced in star-forming regions, including organic molecules called polycyclic aromatic hydrocarbons, or PAHs. PAHs are also found on Earth, in car exhaust and on burnt toast, among other places. Here, the PAHs are being heated up by the young stars, and, as a result, shine in infrared light. This image was taken by the infrared array camera on Spitzer. It is a 4-color composite of infrared light, showing emissions from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange), and 8.0 microns (red). Starlight has been subtracted from the orange and red channels in order to enhance the dust, or PAH, features. |
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Amazing Andromeda Galaxy
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Amazing Andromeda Galaxy |
| Description |
The many "personalities" of our great galactic neighbor, the Andromeda galaxy, are exposed in this new composite image from NASA's Galaxy Evolution Explorer and the Spitzer Space Telescope. The wide, ultraviolet eyes of Galaxy Evolution Explorer reveal Andromeda's "fiery" nature -- hotter regions brimming with young and old stars. In contrast, Spitzer's super-sensitive infrared eyes show Andromeda's relatively "cool" side, which includes embryonic stars hidden in their dusty cocoons. Galaxy Evolution Explorer detected young, hot, high-mass stars, which are represented in blue, while populations of relatively older stars are shown as green dots. The bright yellow spot at the galaxy's center depicts a particularly dense population of old stars. Swaths of red in the galaxy's disk indicate areas where Spitzer found cool, dusty regions where stars are forming. These stars are still shrouded by the cosmic clouds of dust and gas that collapsed to form them. Together, Galaxy Evolution Explorer and Spitzer complete the picture of Andromeda's swirling spiral arms. Hints of pinkish purple depict regions where the galaxy's populations of hot, high-mass stars and cooler, dust-enshrouded stars co-exist. Located 2.5 million light-years away, the Andromeda is our largest nearby galactic neighbor. The galaxy's entire disk spans about 260,000 light-years, which means that a light beam would take 260,000 years to travel from one end of the galaxy to the other. By comparison, our Milky Way galaxy's disk is about 100,000 light-years across. This image is a false color composite comprised of data from Galaxy Evolution Explorer's far-ultraviolet detector (blue), near-ultraviolet detector (green), and Spitzer's multiband imaging photometer at 24 microns (red). |
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Andromeda Makes a Splash
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Andromeda Makes a Splash |
| Description |
This infrared composite image from NASA's Spitzer Space Telescope shows the Andromeda galaxy, a neighbor to our Milky Way galaxy. The main image (top) highlights the contrast between the galaxy's choppy waves of dust (red) and smooth sea of older stars (blue). The panels below the main image show the galaxy's older stars (left) and dust (right) separately. Spiral galaxies tend to form new stars in their dusty, clumpy arms, while their cores are populated by older stars. The Spitzer view also shows Andromeda's dust lanes twisting all the way into the center of the galaxy, a region that is crammed full of stars. In visible-light pictures, this central region tends to be dominated by starlight. Astronomers used these new images to measure the total infrared brightness of Andromeda. Because the amount of infrared light given off by stars depends on their masses, the brightness measurements provided a novel method for "weighing" the Andromeda galaxy. According to this method, the mass of the stars in Andromeda is about110 billion times that of the sun, which is in agreement with past calculations. This means the galaxy contains about one trillion stars (because most stars are actually less massive than the sun). For comparison, the Milky Way is estimated to hold about 400 billion stars. A small, companion galaxy called NGC 205 is visible above Andromeda. Another companion galaxy called M32 can also been seen below the galaxy. The Andromeda galaxy, also known affectionately by astronomers as Messier 31, is located 2.5 million light-years away in the constellation Andromeda. It is the closest major galaxy to the Milky Way, making it the ideal specimen for carefully examining the nature of galaxies. On a clear, dark night, the galaxy can be spotted with the naked eye as a fuzzy blob. Andromeda's entire disk spans about 260,000 light-years, which means that a light beam would take 260,000 years to travel from one end of the galaxy to the other. By comparison, the Milky Way is about 100,000 light-years across. When viewed from Earth, Andromeda occupies a portion of the sky equivalent to seven full moons. Because this galaxy is so large, the infrared images had to be stitched together out of about 3,000 separate Spitzer exposures. The light detected by Spitzer's infrared array camera at 3.6 and 4.5 microns is sensitive mostly to starlight and is shown in blue and green, respectively. The 8-micron light shows warm dust and is shown in red. The contribution from starlight has been subtracted from the 8-micron image to better highlight the dust structures. |
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Andromeda Makes a Splash
| Title |
Andromeda Makes a Splash |
| Description |
This infrared composite image from NASA's Spitzer Space Telescope shows the Andromeda galaxy, a neighbor to our Milky Way galaxy. The main image (top) highlights the contrast between the galaxy's choppy waves of dust (red) and smooth sea of older stars (blue). The panels below the main image show the galaxy's older stars (left) and dust (right) separately. Spiral galaxies tend to form new stars in their dusty, clumpy arms, while their cores are populated by older stars. The Spitzer view also shows Andromeda's dust lanes twisting all the way into the center of the galaxy, a region that is crammed full of stars. In visible-light pictures, this central region tends to be dominated by starlight. Astronomers used these new images to measure the total infrared brightness of Andromeda. Because the amount of infrared light given off by stars depends on their masses, the brightness measurements provided a novel method for "weighing" the Andromeda galaxy. According to this method, the mass of the stars in Andromeda is about110 billion times that of the sun, which is in agreement with past calculations. This means the galaxy contains about one trillion stars (because most stars are actually less massive than the sun). For comparison, the Milky Way is estimated to hold about 400 billion stars. A small, companion galaxy called NGC 205 is visible above Andromeda. Another companion galaxy called M32 can also been seen below the galaxy. The Andromeda galaxy, also known affectionately by astronomers as Messier 31, is located 2.5 million light-years away in the constellation Andromeda. It is the closest major galaxy to the Milky Way, making it the ideal specimen for carefully examining the nature of galaxies. On a clear, dark night, the galaxy can be spotted with the naked eye as a fuzzy blob. Andromeda's entire disk spans about 260,000 light-years, which means that a light beam would take 260,000 years to travel from one end of the galaxy to the other. By comparison, the Milky Way is about 100,000 light-years across. When viewed from Earth, Andromeda occupies a portion of the sky equivalent to seven full moons. Because this galaxy is so large, the infrared images had to be stitched together out of about 3,000 separate Spitzer exposures. The light detected by Spitzer's infrared array camera at 3.6 and 4.5 microns is sensitive mostly to starlight and is shown in blue and green, respectively. The 8-micron light shows warm dust and is shown in red. The contribution from starlight has been subtracted from the 8-micron image to better highlight the dust structures. |
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Andromeda Makes a Splash
| Title |
Andromeda Makes a Splash |
| Description |
This infrared composite image from NASA's Spitzer Space Telescope shows the Andromeda galaxy, a neighbor to our Milky Way galaxy. The main image (top) highlights the contrast between the galaxy's choppy waves of dust (red) and smooth sea of older stars (blue). The panels below the main image show the galaxy's older stars (left) and dust (right) separately. Spiral galaxies tend to form new stars in their dusty, clumpy arms, while their cores are populated by older stars. The Spitzer view also shows Andromeda's dust lanes twisting all the way into the center of the galaxy, a region that is crammed full of stars. In visible-light pictures, this central region tends to be dominated by starlight. Astronomers used these new images to measure the total infrared brightness of Andromeda. Because the amount of infrared light given off by stars depends on their masses, the brightness measurements provided a novel method for "weighing" the Andromeda galaxy. According to this method, the mass of the stars in Andromeda is about110 billion times that of the sun, which is in agreement with past calculations. This means the galaxy contains about one trillion stars (because most stars are actually less massive than the sun). For comparison, the Milky Way is estimated to hold about 400 billion stars. A small, companion galaxy called NGC 205 is visible above Andromeda. Another companion galaxy called M32 can also been seen below the galaxy. The Andromeda galaxy, also known affectionately by astronomers as Messier 31, is located 2.5 million light-years away in the constellation Andromeda. It is the closest major galaxy to the Milky Way, making it the ideal specimen for carefully examining the nature of galaxies. On a clear, dark night, the galaxy can be spotted with the naked eye as a fuzzy blob. Andromeda's entire disk spans about 260,000 light-years, which means that a light beam would take 260,000 years to travel from one end of the galaxy to the other. By comparison, the Milky Way is about 100,000 light-years across. When viewed from Earth, Andromeda occupies a portion of the sky equivalent to seven full moons. Because this galaxy is so large, the infrared images had to be stitched together out of about 3,000 separate Spitzer exposures. The light detected by Spitzer's infrared array camera at 3.6 and 4.5 microns is sensitive mostly to starlight and is shown in blue and green, respectively. The 8-micron light shows warm dust and is shown in red. The contribution from starlight has been subtracted from the 8-micron image to better highlight the dust structures. |
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Andromeda Makes a Splash
| Title |
Andromeda Makes a Splash |
| Description |
This infrared composite image from NASA's Spitzer Space Telescope shows the Andromeda galaxy, a neighbor to our Milky Way galaxy. The main image (top) highlights the contrast between the galaxy's choppy waves of dust (red) and smooth sea of older stars (blue). The panels below the main image show the galaxy's older stars (left) and dust (right) separately. Spiral galaxies tend to form new stars in their dusty, clumpy arms, while their cores are populated by older stars. The Spitzer view also shows Andromeda's dust lanes twisting all the way into the center of the galaxy, a region that is crammed full of stars. In visible-light pictures, this central region tends to be dominated by starlight. Astronomers used these new images to measure the total infrared brightness of Andromeda. Because the amount of infrared light given off by stars depends on their masses, the brightness measurements provided a novel method for "weighing" the Andromeda galaxy. According to this method, the mass of the stars in Andromeda is about110 billion times that of the sun, which is in agreement with past calculations. This means the galaxy contains about one trillion stars (because most stars are actually less massive than the sun). For comparison, the Milky Way is estimated to hold about 400 billion stars. A small, companion galaxy called NGC 205 is visible above Andromeda. Another companion galaxy called M32 can also been seen below the galaxy. The Andromeda galaxy, also known affectionately by astronomers as Messier 31, is located 2.5 million light-years away in the constellation Andromeda. It is the closest major galaxy to the Milky Way, making it the ideal specimen for carefully examining the nature of galaxies. On a clear, dark night, the galaxy can be spotted with the naked eye as a fuzzy blob. Andromeda's entire disk spans about 260,000 light-years, which means that a light beam would take 260,000 years to travel from one end of the galaxy to the other. By comparison, the Milky Way is about 100,000 light-years across. When viewed from Earth, Andromeda occupies a portion of the sky equivalent to seven full moons. Because this galaxy is so large, the infrared images had to be stitched together out of about 3,000 separate Spitzer exposures. The light detected by Spitzer's infrared array camera at 3.6 and 4.5 microns is sensitive mostly to starlight and is shown in blue and green, respectively. The 8-micron light shows warm dust and is shown in red. The contribution from starlight has been subtracted from the 8-micron image to better highlight the dust structures. |
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Hubble Discovers Black Holes
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Hubble Discovers Black Holes in Unexpected Places |
| General Information |
What is a Space Science Update? Major Hubble discoveries on NASA television ... Astronomers explain their Hubble discoveries at a press conference, called a Space Science Update (SSU), broadcast on NASA television. The SSU includes a question and answer session with members of the media. Back to top [ #top ] |
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Hubble Discovers Black Holes
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| Title |
Hubble Discovers Black Holes in Unexpected Places |
| General Information |
What is a Space Science Update? Major Hubble discoveries on NASA television ... Astronomers explain their Hubble discoveries at a press conference, called a Space Science Update (SSU), broadcast on NASA television. The SSU includes a question and answer session with members of the media. Back to top [ #top ] |
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Hubble Discovers Black Holes
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| Title |
Hubble Discovers Black Holes in Unexpected Places |
| General Information |
What is a Space Science Update? Major Hubble discoveries on NASA television ... Astronomers explain their Hubble discoveries at a press conference, called a Space Science Update (SSU), broadcast on NASA television. The SSU includes a question and answer session with members of the media. Back to top [ #top ] |
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Hubble Discovers Black Holes
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| Title |
Hubble Discovers Black Holes in Unexpected Places |
| General Information |
What is a Space Science Update? Major Hubble discoveries on NASA television ... Astronomers explain their Hubble discoveries at a press conference, called a Space Science Update (SSU), broadcast on NASA television. The SSU includes a question and answer session with members of the media. Back to top [ #top ] |
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Hubble Discovers Black Holes
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| Title |
Hubble Discovers Black Holes in Unexpected Places |
| General Information |
What is a Space Science Update? Major Hubble discoveries on NASA television ... Astronomers explain their Hubble discoveries at a press conference, called a Space Science Update (SSU), broadcast on NASA television. The SSU includes a question and answer session with members of the media. Back to top [ #top ] |
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Hubble Discovers Black Holes
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| Title |
Hubble Discovers Black Holes in Unexpected Places |
| General Information |
What is a Space Science Update? Major Hubble discoveries on NASA television ... Astronomers explain their Hubble discoveries at a press conference, called a Space Science Update (SSU), broadcast on NASA television. The SSU includes a question and answer session with members of the media. Back to top [ #top ] |
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Hubble Discovers Black Holes
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| Title |
Hubble Discovers Black Holes in Unexpected Places |
| General Information |
What is a Space Science Update? Major Hubble discoveries on NASA television ... Astronomers explain their Hubble discoveries at a press conference, called a Space Science Update (SSU), broadcast on NASA television. The SSU includes a question and answer session with members of the media. Back to top [ #top ] |
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Hubble Discovers Black Holes
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| Title |
Hubble Discovers Black Holes in Unexpected Places |
| General Information |
What is a Space Science Update? Major Hubble discoveries on NASA television ... Astronomers explain their Hubble discoveries at a press conference, called a Space Science Update (SSU), broadcast on NASA television. The SSU includes a question and answer session with members of the media. Back to top [ #top ] |
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Hubble Discovers Black Holes
…
| Title |
Hubble Discovers Black Holes in Unexpected Places |
| General Information |
What is a Space Science Update? Major Hubble discoveries on NASA television ... Astronomers explain their Hubble discoveries at a press conference, called a Space Science Update (SSU), broadcast on NASA television. The SSU includes a question and answer session with members of the media. Back to top [ #top ] |
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Hubble Discovers Black Holes
…
| Title |
Hubble Discovers Black Holes in Unexpected Places |
| General Information |
What is a Space Science Update? Major Hubble discoveries on NASA television ... Astronomers explain their Hubble discoveries at a press conference, called a Space Science Update (SSU), broadcast on NASA television. The SSU includes a question and answer session with members of the media. Back to top [ #top ] |
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Firestorm of Star Birth Seen
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| Title |
Firestorm of Star Birth Seen in a Local Galaxy |
| 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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Nearby Spiral Galaxy NGC 494
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| Title |
Nearby Spiral Galaxy NGC 4945 |
| Explanation |
For such a close galaxy, NGC 4945 is easy to miss. NGC 4945 [ http://www.ast.cam.ac.uk/AAO/images/captions/aat101.html ] is a spiral galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap980525.html ] in the Centaurus Group of galaxies, located only six times farther away than the prominent Andromeda Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap991114.html ]. The thin disk galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap020703.html ] is oriented nearly edge-on, however, and shrouded in dark dust [ http://antwrp.gsfc.nasa.gov/apod/ap990509.html ]. Therefore galaxy-gazers searching the southern constellation of Centaurus [ http://www.astro.wisc.edu/~dolan/constellations/constellations/Centaurus.html ] need a telescope to see it. The above picture [ http://www.eso.org/outreach/press-rel/pr-1999/phot-18-99.html ] was taken with a large telescope [ http://www.ls.eso.org/lasilla/Telescopes/2p2T/E2p2M/ ] testing a new wide-angle, high-resolution CCD camera [ http://www.ls.eso.org/lasilla/Telescopes/2p2T/E2p2M/WFI/ ]. Most of the spots scattered about the frame [ http://www.eso.org/outreach/epr/posters/ ] are foreground stars in our own Galaxy [ http://antwrp.gsfc.nasa.gov/apod/milky_way.html ], but some spots are globular clusters [ http://antwrp.gsfc.nasa.gov/apod/globular_clusters.html ] orbiting the distant galaxy. NGC 4945 [ http://astro.ph.unimelb.edu.au/central/images/mbrown/ngc4945.html ] is thought to be quite similar to our own Milky Way Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap971229.html ]. X-ray [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/emspectrum.html ] observations reveal, however, that NGC 4945 has an unusual, energetic, Seyfert [ http://antwrp.gsfc.nasa.gov/apod/ap010701.html ] 2 nucleus that might house a large black hole [ http://antwrp.gsfc.nasa.gov/apod/ap960911.html ]. |
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NGC 6946: The Fireworks Gala
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NGC 6946: The Fireworks Galaxy |
| Explanation |
Why is this galaxy so active? Nearby spiral galaxy NGC 6946 [ http://www.noao.edu/outreach/aop/observers/n6946.html ] is undergoing a tremendous burst of star formation with no obvious cause. In many cases spirals light up when interacting with another galaxy, but NGC 6946 [ http://antwrp.gsfc.nasa.gov/apod/ap040410.html ] appears relatively isolated in space. Located just 10 million light years [ http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question19.html ] away toward the constellation [ http://www.fillingthesky.com/id8.html ] of Cepheus [ http://www.astronomical.org/portal/modules/wfsection/article.php?articleid=20 ], this beautiful face-on spiral [ http://antwrp.gsfc.nasa.gov/apod/ap041216.html ] spans about 20,000 light years and is seen through a field of foreground stars from our Milky Way Galaxy [ http://cassfos02.ucsd.edu/public/tutorial/MW.html ]. The center of NGC 6946 [ http://www.gemini.edu/index.php?option=content&task=view&id=116 ] is home to a nuclear starburst itself, and picturesque dark dust is seen lacing the disk along with bright blue stars [ http://antwrp.gsfc.nasa.gov/apod/ap031227.html ], red emission nebulas [ http://antwrp.gsfc.nasa.gov/apod/emission_nebulae.html ], fast moving gas clouds, and unusually frequent supernovas [ http://heasarc.gsfc.nasa.gov/docs/snr.html ]. The 8-meter Gemini North Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap990629.html ] in Hawaii, USA [ http://www.cia.gov/cia/publications/factbook/geos/us.html ], took the above image [ http://www.gemini.edu/index.php?set_albumName=Previous-Featured-Images&id=ngc6946_Small&option=com_gallery&Itemid=39&include=view_photo.php ]. A suggested explanation [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2000MNRAS.319..821P ] for the high star formation rate is the recent accretion of many primordial low-mass neutral hydrogen clouds [ http://www.universetoday.com/am/publish/clouds_hydrogen_swarm_andromeda.html?422004 ] from the surrounding region. |
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Nearby Spiral Galaxy NGC 494
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| Title |
Nearby Spiral Galaxy NGC 4945 |
| Explanation |
For such a close galaxy, NGC 4945 is easy to miss. NGC 4945 [ http://www.aao.gov.au/local/www/dfm/aat101.html ] is a spiral galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap980525.html ] in the Centaurus Group of galaxies, located only six times farther away than the prominent Andromeda Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap971101.html ]. The thin disk galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap981220.html ] is oriented nearly edge-on, however, and shrouded in dark dust [ http://antwrp.gsfc.nasa.gov/apod/ap980104.html ]. Therefore galaxy-gazers searching the southern constellation of Centaurus [ http://www.astro.wisc.edu/~dolan/constellations/constellations/Centaurus.html ] need a telescope to see it. The above picture [ http://www.eso.org/outreach/press-rel/pr-1999/phot-18-99.html ] was taken with a large telescope [ http://www.ls.eso.org/lasilla/Telescopes/2p2T/E2p2M/E2p2M.html ] testing a new wide-angle, high-resolution CCD camera [ http://www.ls.eso.org/lasilla/Telescopes/2p2T/E2p2M/WFI/WFI.html ]. Most of the spots scattered about the frame are foreground stars in our own Galaxy, but some spots are globular clusters [ http://antwrp.gsfc.nasa.gov/apod/ap980719.html ] orbiting the distant galaxy. NGC 4945 [ http://astro.ph.unimelb.edu.au/central/images/mbrown/ngc4945.html ] is thought to be quite similar to our own Milky Way Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap971229.html ]. X-ray [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/emspectrum.html ] observations reveal, however, that NGC 4945 has an unusual, energetic, Seyfert [ http://antwrp.gsfc.nasa.gov/apod/ap981023.html ] 2 nucleus that might house a large black hole [ http://antwrp.gsfc.nasa.gov/apod/ap960911.html ]. |
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