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Andromeda and Earth of Goddard Space Flight Center (GSFC)
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Deepest View of Space Yields
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| Title |
Deepest View of Space Yields Young Stars in Andromeda Halo |
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Deepest View of Space Yields
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| Title |
Deepest View of Space Yields Young Stars in Andromeda Halo |
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Hubble Finds Mysterious Disk
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Hubble Finds Mysterious Disk of Blue Stars Around Black Hole |
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STEREO Coronal Mass Ejection
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| Title |
STEREO Coronal Mass Ejection: From the EUVI to HI-2 |
| Abstract |
This movie collects imagery from SOHO and STEREO-A of a coronal mass ejection (CME) during January of 2007. The instruments in this view, from left to right, are STEREO/HI-1, STEREO/HI-2, SOHO/LASCO/C3, SOHO/LASCO/C2, and STEREO/EUVI. The Heliospheric Imager, HI-2, shows some of the tail of comet McNaught. The dark trapezoidal shape on the left edge of the image in HI-2 is the Earth occulter which will block out the disk of the Earth when it moves into view (since the planet will appear so bright as to saturate the detectors). Due to ongoing work with the STEREO coronagraphs, COR1 and COR2, the SOHO/LASCO coronagraphs are used for this movie. The blue Sun in the center of the coronagraphs is STEREO/EUVI ultraviolet images. There is a 22 hour gap in the data coverage for HI-2 which creates the appearance of a jump in the playback. These are not standard images but are called `running difference' images which highlight changes in the view. White pixels correspond to increases in brightness, while dark pixels reflect a decrease in brightness, with respect to the immediately previous image. 'Running differencing' generates some unusual effects. For example, the mottled background is created by the motion of the stars through the field-of-view as the spacecraft pointing direction slowly changes (the Andromeda galaxy is the oblong 'smudge' near the upper left corner). The planets Venus (right edge of HI-2) and Mercury are visible (near center of HI-1), their column of pixels saturated due to their brightness. * STEREO: Solar TErrestrial RElations Observatory * SOHO: SOlar Heliospheric Observatory * LASCO: Large Angle and Spectrometric Coronagraph * EUVI: Extreme UltraViolet Imager |
| Completed |
2007-02-26 |
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STEREO Coronal Mass Ejection
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| Title |
STEREO Coronal Mass Ejection: From the EUVI to HI-2 |
| Abstract |
This movie collects imagery from SOHO and STEREO-A of a coronal mass ejection (CME) during January of 2007. The instruments in this view, from left to right, are STEREO/HI-1, STEREO/HI-2, SOHO/LASCO/C3, SOHO/LASCO/C2, and STEREO/EUVI. The Heliospheric Imager, HI-2, shows some of the tail of comet McNaught. The dark trapezoidal shape on the left edge of the image in HI-2 is the Earth occulter which will block out the disk of the Earth when it moves into view (since the planet will appear so bright as to saturate the detectors). Due to ongoing work with the STEREO coronagraphs, COR1 and COR2, the SOHO/LASCO coronagraphs are used for this movie. The blue Sun in the center of the coronagraphs is STEREO/EUVI ultraviolet images. There is a 22 hour gap in the data coverage for HI-2 which creates the appearance of a jump in the playback. These are not standard images but are called `running difference' images which highlight changes in the view. White pixels correspond to increases in brightness, while dark pixels reflect a decrease in brightness, with respect to the immediately previous image. 'Running differencing' generates some unusual effects. For example, the mottled background is created by the motion of the stars through the field-of-view as the spacecraft pointing direction slowly changes (the Andromeda galaxy is the oblong 'smudge' near the upper left corner). The planets Venus (right edge of HI-2) and Mercury are visible (near center of HI-1), their column of pixels saturated due to their brightness. * STEREO: Solar TErrestrial RElations Observatory * SOHO: SOlar Heliospheric Observatory * LASCO: Large Angle and Spectrometric Coronagraph * EUVI: Extreme UltraViolet Imager |
| Completed |
2007-02-26 |
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STEREO Coronal Mass Ejection
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| Title |
STEREO Coronal Mass Ejection: From the EUVI to HI-2 |
| Abstract |
This movie collects imagery from SOHO and STEREO-A of a coronal mass ejection (CME) during January of 2007. The instruments in this view, from left to right, are STEREO/HI-1, STEREO/HI-2, SOHO/LASCO/C3, SOHO/LASCO/C2, and STEREO/EUVI. The Heliospheric Imager, HI-2, shows some of the tail of comet McNaught. The dark trapezoidal shape on the left edge of the image in HI-2 is the Earth occulter which will block out the disk of the Earth when it moves into view (since the planet will appear so bright as to saturate the detectors). Due to ongoing work with the STEREO coronagraphs, COR1 and COR2, the SOHO/LASCO coronagraphs are used for this movie. The blue Sun in the center of the coronagraphs is STEREO/EUVI ultraviolet images. There is a 22 hour gap in the data coverage for HI-2 which creates the appearance of a jump in the playback. These are not standard images but are called `running difference' images which highlight changes in the view. White pixels correspond to increases in brightness, while dark pixels reflect a decrease in brightness, with respect to the immediately previous image. 'Running differencing' generates some unusual effects. For example, the mottled background is created by the motion of the stars through the field-of-view as the spacecraft pointing direction slowly changes (the Andromeda galaxy is the oblong 'smudge' near the upper left corner). The planets Venus (right edge of HI-2) and Mercury are visible (near center of HI-1), their column of pixels saturated due to their brightness. * STEREO: Solar TErrestrial RElations Observatory * SOHO: SOlar Heliospheric Observatory * LASCO: Large Angle and Spectrometric Coronagraph * EUVI: Extreme UltraViolet Imager |
| Completed |
2007-02-26 |
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STEREO Coronal Mass Ejection
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| Title |
STEREO Coronal Mass Ejection: From the EUVI to HI-2 |
| Abstract |
This movie collects imagery from SOHO and STEREO-A of a coronal mass ejection (CME) during January of 2007. The instruments in this view, from left to right, are STEREO/HI-1, STEREO/HI-2, SOHO/LASCO/C3, SOHO/LASCO/C2, and STEREO/EUVI. The Heliospheric Imager, HI-2, shows some of the tail of comet McNaught. The dark trapezoidal shape on the left edge of the image in HI-2 is the Earth occulter which will block out the disk of the Earth when it moves into view (since the planet will appear so bright as to saturate the detectors). Due to ongoing work with the STEREO coronagraphs, COR1 and COR2, the SOHO/LASCO coronagraphs are used for this movie. The blue Sun in the center of the coronagraphs is STEREO/EUVI ultraviolet images. There is a 22 hour gap in the data coverage for HI-2 which creates the appearance of a jump in the playback. These are not standard images but are called `running difference' images which highlight changes in the view. White pixels correspond to increases in brightness, while dark pixels reflect a decrease in brightness, with respect to the immediately previous image. 'Running differencing' generates some unusual effects. For example, the mottled background is created by the motion of the stars through the field-of-view as the spacecraft pointing direction slowly changes (the Andromeda galaxy is the oblong 'smudge' near the upper left corner). The planets Venus (right edge of HI-2) and Mercury are visible (near center of HI-1), their column of pixels saturated due to their brightness. * STEREO: Solar TErrestrial RElations Observatory * SOHO: SOlar Heliospheric Observatory * LASCO: Large Angle and Spectrometric Coronagraph * EUVI: Extreme UltraViolet Imager |
| Completed |
2007-02-26 |
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STEREO Coronal Mass Ejection
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| Title |
STEREO Coronal Mass Ejection: From the EUVI to HI-2 |
| Abstract |
This movie collects imagery from SOHO and STEREO-A of a coronal mass ejection (CME) during January of 2007. The instruments in this view, from left to right, are STEREO/HI-1, STEREO/HI-2, SOHO/LASCO/C3, SOHO/LASCO/C2, and STEREO/EUVI. The Heliospheric Imager, HI-2, shows some of the tail of comet McNaught. The dark trapezoidal shape on the left edge of the image in HI-2 is the Earth occulter which will block out the disk of the Earth when it moves into view (since the planet will appear so bright as to saturate the detectors). Due to ongoing work with the STEREO coronagraphs, COR1 and COR2, the SOHO/LASCO coronagraphs are used for this movie. The blue Sun in the center of the coronagraphs is STEREO/EUVI ultraviolet images. There is a 22 hour gap in the data coverage for HI-2 which creates the appearance of a jump in the playback. These are not standard images but are called `running difference' images which highlight changes in the view. White pixels correspond to increases in brightness, while dark pixels reflect a decrease in brightness, with respect to the immediately previous image. 'Running differencing' generates some unusual effects. For example, the mottled background is created by the motion of the stars through the field-of-view as the spacecraft pointing direction slowly changes (the Andromeda galaxy is the oblong 'smudge' near the upper left corner). The planets Venus (right edge of HI-2) and Mercury are visible (near center of HI-1), their column of pixels saturated due to their brightness. * STEREO: Solar TErrestrial RElations Observatory * SOHO: SOlar Heliospheric Observatory * LASCO: Large Angle and Spectrometric Coronagraph * EUVI: Extreme UltraViolet Imager |
| Completed |
2007-02-26 |
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STEREO Coronal Mass Ejection
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| Title |
STEREO Coronal Mass Ejection: From the EUVI to HI-2 |
| Abstract |
This movie collects imagery from SOHO and STEREO-A of a coronal mass ejection (CME) during January of 2007. The instruments in this view, from left to right, are STEREO/HI-1, STEREO/HI-2, SOHO/LASCO/C3, SOHO/LASCO/C2, and STEREO/EUVI. The Heliospheric Imager, HI-2, shows some of the tail of comet McNaught. The dark trapezoidal shape on the left edge of the image in HI-2 is the Earth occulter which will block out the disk of the Earth when it moves into view (since the planet will appear so bright as to saturate the detectors). Due to ongoing work with the STEREO coronagraphs, COR1 and COR2, the SOHO/LASCO coronagraphs are used for this movie. The blue Sun in the center of the coronagraphs is STEREO/EUVI ultraviolet images. There is a 22 hour gap in the data coverage for HI-2 which creates the appearance of a jump in the playback. These are not standard images but are called `running difference' images which highlight changes in the view. White pixels correspond to increases in brightness, while dark pixels reflect a decrease in brightness, with respect to the immediately previous image. 'Running differencing' generates some unusual effects. For example, the mottled background is created by the motion of the stars through the field-of-view as the spacecraft pointing direction slowly changes (the Andromeda galaxy is the oblong 'smudge' near the upper left corner). The planets Venus (right edge of HI-2) and Mercury are visible (near center of HI-1), their column of pixels saturated due to their brightness. * STEREO: Solar TErrestrial RElations Observatory * SOHO: SOlar Heliospheric Observatory * LASCO: Large Angle and Spectrometric Coronagraph * EUVI: Extreme UltraViolet Imager |
| Completed |
2007-02-26 |
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The Comet and the Galaxy
| Title |
The Comet and the Galaxy |
| Explanation |
The Moon almost ruined this photograph. During late March and early April 1997, Comet Hale-Bopp [ http://www.jpl.nasa.gov/comet/ ] passed nearly in front of the Andromeda Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap040718.html ]. Here the Great Comet of 1997 [ http://cometography.com/lcomets/1995o1.html ] and the Great Galaxy in Andromeda [ http://www.seds.org/messier/m/m031.html ] were photographed together [ http://antwrp.gsfc.nasa.gov/apod/ap970401.html ] on 1997 March 24th. The problem was the brightness of the Moon [ http://antwrp.gsfc.nasa.gov/apod/ap970924.html ]. The Moon [ http://www.seds.org/nineplanets/nineplanets/luna.html ] was full that night and so bright that long exposures meant to capture the tails of Hale-Bopp [ http://antwrp.gsfc.nasa.gov/apod/ap970416.html ] and the disk of M31 [ http://antwrp.gsfc.nasa.gov/apod/ap961011.html ] would capture instead only moonlight reflected off the Earth's atmosphere. By the time the Moon would set, this opportunity would be gone. That's why this picture was taken during a total lunar eclipse [ http://antwrp.gsfc.nasa.gov/apod/ap960926.html ]. |
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M33: Spiral Galaxy in Triang
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| Title |
M33: Spiral Galaxy in Triangulum |
| Explanation |
The small, northern constellation Triangulum [ http://www.hawastsoc.org/deepsky/tri/index.html ] harbors this magnificent face-on spiral galaxy, M33. Its popular names include the Pinwheel Galaxy or just the Triangulum Galaxy [ http://www.seds.org/messier/m/m033.html ]. M33 is over 50,000 light-years in diameter, third largest in the Local Group [ http://atlasoftheuniverse.com/localgr.html ] of galaxies after the Andromeda Galaxy (M31), and our own Milky Way. About 3 million light-years from the Milky Way, M33 is itself thought to be a satellite of the Andromeda Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap021021.html ] and astronomers [ http://arxiv.org/abs/astro-ph?papernum=0506609 ] in these two galaxies would likely have spectacular views of each other's grand spiral star systems. As for the view from planet Earth, this detailed, wide field image [ http://www.tvdavisastropics.com/astroimages-1_00001f.htm ] nicely shows off M33's blue star clusters and pinkish star [ http://www.astropix.com/HTML/SHOW_DIG/031.HTM ] forming regions which trace the galaxy's loosely wound spiral arms. In fact, the cavernous NGC 604 [ http://antwrp.gsfc.nasa.gov/apod/ap021102.html ] is the brightest star forming region, seen here at about the 1 o'clock position from the galaxy center. Like M31, M33's population of well-measured variable stars have helped make this nearby spiral a cosmic yardstick [ http://cfa-www.harvard.edu/~kstanek/DIRECT/ ] for establishing [ http://adsabs.harvard.edu/cgi-bin/ bib_query?1926ApJ....63..236H ] the distance scale [ http://antwrp.gsfc.nasa.gov/diamond_jubilee/ debate96.html ] of the Universe. |
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Moon Over Andromeda
| Title |
Moon Over Andromeda |
| Explanation |
The Great Spiral Galaxy in Andromeda [ http://antwrp.gsfc.nasa.gov/apod/ap051222.html ] (aka M31), a mere 2.5 million light-years distant [ http://arxiv.org/abs/astro-ph/0511045 ], is the closest large spiral to our own Milky Way. Andromeda is visible to the unaided eye as a small, faint, fuzzy patch, but because its surface brightness is so low, casual skygazers [ http://www.physics.ucla.edu/~huffman/m31.html ] can't appreciate the galaxy's impressive extent in planet Earth's sky. This entertaining composite image compares the angular size [ http://chandra.harvard.edu/photo/scale.html ] of the nearby galaxy to a brighter, more familiar celestial sight. In it, a deep exposure of Andromeda [ http://www.caelumobservatory.com/gallery/m31abtp.shtml ], tracing beautiful blue star clusters in spiral arms far beyond the bright yellow core, is combined with a typical view of a nearly full Moon. Shown at the same angular scale, the Moon covers about 1/2 degree on the sky, while the galaxy is clearly [ http://www.regulusastro.com/regulus/papers/ m31/ ] several times that size. The deep Andromeda exposure also includes two bright satellite galaxies, M32 [ http://antwrp.gsfc.nasa.gov/apod/ap991103.html ] and M110 [ http://antwrp.gsfc.nasa.gov/apod/ap060908.html ] (bottom). |
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Hale-Bopp: The Great Comet o
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| Title |
Hale-Bopp: The Great Comet of 1997 |
| Explanation |
Ten short years ago, Comet Hale-Bopp [ http://www.cometography.com/lcomets/1995o1.html ] rounded the Sun and offered a dazzling spectacle in planet Earth's night. This stunning view [ http://www.astropix.com/HTML/SHOWCASE/970401.HTM ], recorded shortly after the comet's perihelion passage on April 1, 1997, features the memorable tails [ http://www.ifa.hawaii.edu/~jewitt/tail.html ] of Hale-Bopp -- a whitish dust tail and blue ion tail. Here, the ion tail extends well over ten degrees across the northern sky, fading near the double star clusters [ http://antwrp.gsfc.nasa.gov/apod/ap060413.html ] in Perseus, while the head of the comet lies near Almach [ http://www.astro.uiuc.edu/~kaler/sow/almach.html ], a bright star in the constellation Andromeda. Do you remember Hale-Bopp [ http://antwrp.gsfc.nasa.gov/apod/ap970416.html ]? The photographer's sons do, pictured in the foreground at ages 12 and 15. In all, Hale-Bopp [ http://antwrp.gsfc.nasa.gov/apod/ap970328.html ] was reported as visible to the naked eye from roughly late May 1996 through September 1997. |
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A Galaxy is not a Comet
| Title |
A Galaxy is not a Comet |
| Explanation |
This gorgeous galaxy and comet portrait [ http://science.nasa.gov/spaceweather/comets/ gallery_iz.html ] was recorded on April 5th in the skies over the Oriental Pyrenees near Figueres, Spain [ http://www.odci.gov/cia/publications/factbook/geos/ sp.html ]. From a site above 1,100 meters, astrophotographer [ http://www.skylook.net/nav/indexe.htm ] Juan Carlos Casado used a guided time exposure, fast film, and a telephoto lens to capture the predicted conjunction of the bright Comet Ikeya-Zhang [ http://antwrp.gsfc.nasa.gov/apod/ap020404.html ] (right) and the Andromeda Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap000908.html ] (left). This stunning celestial scene would also have been a rewarding one for the influential 18th century comet hunter Charles Messier [ http://www.seds.org/messier/xtra/history/ biograph.html ]. While Messier scanned French skies for comets, he carefully cataloged positions of things which were fuzzy and comet-like in appearance but did not move against the background stars and so were definitely not comets. The Andromeda Galaxy [ http://nedwww.ipac.caltech.edu/level5/ANDROMEDA_Atlas/ frames.html ], also known as M31, is the 31st object in his famous not-a-comet catalog [ http://seds.lpl.arizona.edu/messier/xtra/history/ m-cat.html ]. Not-a-comet object number 110 [ http://www.seds.org/messier/m/ m110.html ], a late addition to Messier's catalog, is one of Andromeda's small satellite galaxies, and can be seen here just below M31. Our modern [ http://antwrp.gsfc.nasa.gov/diamond_jubilee/ debate20.html ] understanding [ http://www.astr.ua.edu/goodies/data_resources/ galaxies.text ] holds that the Andromeda galaxy is a large spiral galaxy some 2 million light-years distant [ http://www.anzwers.org/free/universe/localgr.html ]. The photogenic Comet Ikeya-Zhang [ http://www.stardate.org/nightsky/comet_IZ.html ], now a lovely sight in early morning skies [ http://www.spaceweather.com/images2002/08apr02/ skymap_north.gif ], is about 80 million kilometers (4 light-minutes) from planet Earth. |
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Island Universe, Cosmic Sand
| Title |
Island Universe, Cosmic Sand |
| Explanation |
On August 13, while counting Perseid meteors [ http://comets.amsmeteors.org/meteors/showers/ perseids.html ] under dark [ http://www.darksky.org/ida/darksky/ index.html ], early morning Arizona skies, Rick Scott set out to photograph [ http://members.cox.net/rmscott/ gallery_space_sky02.html ] their fleeting but fiery trails. The equipment he used included a telephoto lens and fast color film. After 21 pictures he'd caught only two meteors, but luckily this was one of them. Tracking the sky, his ten minute long exposure shows a field of many stars in our own Milky Way galaxy [ http://www.seds.org/messier/ more/mw.html ], most too faint to be seen by the unaided eye. Flashing [ http://antwrp.gsfc.nasa.gov/apod/ap990219.html ] from lower left to upper right, the bright meteor would have been an easy eyeful though, as friction with Earth's atmosphere vaporized [ http://antwrp.gsfc.nasa.gov/apod/ap020816.html ] the hurtling grain of cosmic sand [ http://antwrp.gsfc.nasa.gov/apod/ap001117.html ], a piece of dust from Comet Swift-Tuttle [ http://comets.amsmeteors.org/comets/pcomets/ 109p.html ]. Just above and left of center, well beyond the stars of the Milky Way, lies the island universe [ http://antwrp.gsfc.nasa.gov/apod/ap020518.html ] known as M31 or the Andromeda galaxy. The visible meteor trail begins about 100 kilometers above Earth's surface, one of the closest celestial objects seen in the sky. In contrast, Andromeda [ http://www.seds.org/messier/m/ m031.html ], about 2 million light-years away, is the most distant object easily visible to the naked-eye. |
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Island Universe, Cosmic Sand
| Title |
Island Universe, Cosmic Sand |
| Explanation |
On August 13, 2002, while counting Perseid meteors [ http://science.nasa.gov/headlines/y2003/ 17jul_perseids2003.htm ] under dark [ http://www.darksky.org/ida/darksky/ index.html ], early morning Arizona skies, Rick Scott set out to photograph [ http://members.cox.net/rmscott/ gallery_space_sky02.html ] their fleeting but fiery trails. The equipment he used included a telephoto lens and fast color film. After 21 pictures he'd caught only two meteors, but luckily this was one of them. Tracking the sky, his ten minute long exposure shows a field of many stars in our own Milky Way galaxy [ http://www.seds.org/messier/ more/mw.html ], most too faint to be seen by the unaided eye. Flashing [ http://antwrp.gsfc.nasa.gov/apod/ap990219.html ] from lower left to upper right, the bright meteor would have been an easy eyeful though, as friction with Earth's atmosphere vaporized [ http://antwrp.gsfc.nasa.gov/apod/ap020816.html ] the hurtling grain of cosmic sand [ http://antwrp.gsfc.nasa.gov/apod/ap001117.html ], a piece of dust from Comet Swift-Tuttle [ http://comets.amsmeteors.org/comets/pcomets/ 109p.html ]. Just above and left of center, well beyond the stars of the Milky Way, lies the island universe [ http://antwrp.gsfc.nasa.gov/apod/ap020518.html ] known as M31 or the Andromeda galaxy. The visible meteor trail begins about 100 kilometers above Earth's surface, one of the closest celestial objects seen in the sky. In contrast, Andromeda [ http://www.seds.org/messier/m/ m031.html ], about 2 million light-years away, is the most distant object easily visible to the naked-eye. |
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The Northern Milky Way
| Title |
The Northern Milky Way |
| Explanation |
Many of the stars in our home Milky Way Galaxy [ http://www.seds.org/messier/more/mw.html ] appear together as a dim band on the sky that passes nearly over the Earth's north [ http://antwrp.gsfc.nasa.gov/apod/ap020818.html ] and south poles. Pictured above [ http://www.astropix.com/HTML/SHOWCASE/NMW.HTM ] is the part of our Galaxy [ http://antwrp.gsfc.nasa.gov/apod/milky_way.html ] that passes closest over the north pole [ http://antwrp.gsfc.nasa.gov/apod/ap000715.html ]. Placing your cursor [ http://www.hyperdictionary.com/dictionary/cursor] over the image will bring up the names of several constellations [ http://www.adlerplanetarium.org/history/exhibits/constellations/timeline.html ] and bright stars [ http://www.astro.wisc.edu/~dolan/constellations/extra/brightest.html ]. The diffuse white Galaxy glow is created by billions of stars, while red patches are large emission nebulas [ http://antwrp.gsfc.nasa.gov/apod/emission_nebulae.html ], usually marking areas where bright stars have recently formed. In the north, all of the lights visible at night and all lights that created this image were emitted within the past few thousand years from within the Milky Way Galaxy -- except one. On the upper right is a small faint patch designated M31, the Andromeda Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap021021.html ]. M31 is a spiral galaxy [ http://www.seds.org/messier/spir.html ] similar to our Milky Way [ http://antwrp.gsfc.nasa.gov/apod/ap990224.html ] but so distant it emits the oldest light distinguishable by the unaided eye -- light that takes over two million years to reach us. |
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M33: Spiral Galaxy in Triang
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| Title |
M33: Spiral Galaxy in Triangulum |
| Explanation |
The small constellation Triangulum [ http://www.hawastsoc.org/deepsky/tri/index.html ] in the northern sky harbors this magnificent face-on spiral galaxy, M33. Its popular names include the Pinwheel Galaxy or just the Triangulum Galaxy [ http://www.seds.org/messier/m/m033.html ]. M33's diameter spans over 50,000 light-years, making it third largest in the Local Group [ http://www.anzwers.org/free/universe/localgr.html ] of galaxies after the Andromeda Galaxy (M31), and our own Milky Way. About 3 million light-years from the Milky Way, M33 lies very close to the Andromeda Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap021021.html ] and observers [ http://www.astr.ua.edu/gifimages/m33.html ] in these two galaxies would likely have spectacular views of each other's grand spiral star systems. As for the view from planet Earth, this sharp 27 frame mosaic [ http://www.robgendlerastropics.com/M33ColorPage.html ] of M33 nicely shows off blue star clusters and pinkish star forming regions which trace the galaxy's loosely wound spiral arms. In fact, the cavernous NGC 604 [ http://antwrp.gsfc.nasa.gov/apod/ap021102.html ] is the brightest star forming region seen here, visible along an arm arcing above and to the right of the galaxy center. Like M31, M33's population of well-measured variable stars have helped make this nearby spiral a cosmic yardstick [ http://cfa-www.harvard.edu/~kstanek/DIRECT/ ] for establishing [ http://adsabs.harvard.edu/cgi-bin/ bib_query?1926ApJ....63..236H ] the distance scale [ http://antwrp.gsfc.nasa.gov/diamond_jubilee/ debate96.html ] of the Universe. |
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The Andromeda Galaxy from GA
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| Title |
The Andromeda Galaxy from GALEX |
| Explanation |
Why does the Andromeda Galaxy have a giant ring? Viewed in ultraviolet light [ http://imagers.gsfc.nasa.gov/ems/uv.html ], the closest major galaxy to our Milky Way Galaxy [ http://www.seds.org/messier/more/mw.html ] looks more like a ring galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap020909.html ] than a spiral [ http://antwrp.gsfc.nasa.gov/apod/ap030911.html ]. The ring is highlighted beautifully in this newly released image mosaic of Andromeda [ http://antwrp.gsfc.nasa.gov/apod/ap021021.html ] (M31) taken by the GALaxy Evolution Explorer [ http://www.galex.caltech.edu/ABOUT/about.html ] (GALEX), a satellite launched into Earth orbit in April. In the above image [ http://www.galex.caltech.edu/popups/gallery-M31.html ], ultraviolet colors have been digitally shifted to the visual. Young blue stars [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1964ApJS....9...65V ] dominate the image, indicating the star forming ring [ http://antwrp.gsfc.nasa.gov/apod/ap010612.html ] as well as other star forming regions even further from the galactic center [ http://antwrp.gsfc.nasa.gov/apod/ap000121.html ]. The origin of the huge 150,000-light year [ http://chandra.harvard.edu/photo/cosmic_distance.html ] ring is unknown but likely related to gravitational interactions [ http://antwrp.gsfc.nasa.gov/apod/ap020506.html ] with small satellite galaxies [ http://antwrp.gsfc.nasa.gov/apod/ap021202.html ] that orbit near the galactic giant. M31 [ http://www.seds.org/messier/m/m031.html ] lies about three million light-years distant and is bright enough to be seen without binoculars toward the constellation [ http://en2.wikipedia.org/wiki/Constellations ] of Andromeda [ http://www.astronomical.org/constellations/and.html ]. |
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A Galaxy is not a Comet
| Title |
A Galaxy is not a Comet |
| Explanation |
This gorgeous galaxy and comet portrait [ http://science.nasa.gov/spaceweather/comets/ gallery_iz.html ] was recorded on April 5th, 2002, in the skies over the Oriental Pyrenees near Figueres, Spain [ http://www.odci.gov/cia/publications/factbook/geos/ sp.html ]. From a site above 1,100 meters, astrophotographer [ http://www.skylook.net/nav/indexe.htm ] Juan Carlos Casado used a guided time exposure, fast film, and a telephoto lens to capture the predicted conjunction of the bright Comet Ikeya-Zhang [ http://antwrp.gsfc.nasa.gov/apod/ap020404.html ] (right) and the Andromeda Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap021021.html ] (left). This stunning celestial scene would also have been a rewarding one for the influential 18th century comet hunter Charles Messier [ http://www.seds.org/messier/xtra/history/ biograph.html ]. While Messier scanned French skies for comets, he carefully cataloged positions of things which were fuzzy and comet-like in appearance but did not move against the background stars and so were definitely not comets. The Andromeda Galaxy [ http://nedwww.ipac.caltech.edu/level5/ANDROMEDA_Atlas/ frames.html ], also known as M31, is the 31st object in his famous not-a-comet catalog [ http://seds.lpl.arizona.edu/messier/xtra/history/ m-cat.html ]. Not-a-comet object number 110 [ http://www.seds.org/messier/m/ m110.html ], a late addition to Messier's catalog, is one of Andromeda's small satellite galaxies, and can be seen here just below M31. Our modern [ http://antwrp.gsfc.nasa.gov/diamond_jubilee/ debate20.html ] understanding [ http://www.astr.ua.edu/goodies/data_resources/ galaxies.text ] holds that the Andromeda galaxy is a large spiral galaxy some 2 million light-years distant [ http://www.anzwers.org/free/universe/localgr.html ]. The photogenic Comet Ikeya-Zhang [ http://www.stardate.org/nightsky/comet_IZ.html ], then a lovely sight in early morning skies was about 80 million kilometers (4 light-minutes) from planet Earth. |
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The Comet and the Galaxy
| Title |
The Comet and the Galaxy |
| Explanation |
The Moon almost ruined this photograph. During late March and early April 1997, Comet Hale-Bopp [ http://www.jpl.nasa.gov/comet/ ] passed nearly in front of the Andromeda Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap971101.html ]. Here the Great Comet of 1997 [ http://medicine.wustl.edu/~kronkg/1995_O1.html ] and the Great Galaxy in Andromeda [ http://www.seds.org/messier/m/m031.html ] were photographed together [ http://antwrp.gsfc.nasa.gov/apod/ap970401.html ] on 1997 March 24th. The problem was the brightness of the Moon [ http://antwrp.gsfc.nasa.gov/apod/ap970924.html ]. The Moon [ http://www.seds.org/nineplanets/nineplanets/luna.html ] was full that night and so bright that long exposures meant to capture the tails of Hale-Bopp [ http://antwrp.gsfc.nasa.gov/apod/ap970416.html ] and the disk of M31 [ http://antwrp.gsfc.nasa.gov/apod/ap961011.html ] would capture instead only moonlight reflected off the Earth's atmosphere. By the time the Moon would set, this opportunity would be gone. That's why this picture was taken during a lunar eclipse [ http://antwrp.gsfc.nasa.gov/apod/ap960926.html ]. |
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Where is Upsilon Andromedae?
| Title |
Where is Upsilon Andromedae? |
| Explanation |
Astronomers recently announced [ http://cfa-www.harvard.edu/afoe/upsAnd.html ] the detection of three large planets orbiting [ http://antwrp.gsfc.nasa.gov/apod/ap990416.html ] the star Upsilon Andromedae - the first planetary system known to orbit a normal star [ http://www.astro.psu.edu/users/pspm/arecibo/planets/planets.html ] other than our Sun. These planets were [ http://cfa-www.harvard.edu/afoe/espd.html ] not directly photographed but found through a Doppler technique developed to use large telescopes to search nearby stars [ http://www.sciam.com/explorations/052796explorations.html ] for wobbling planetary signatures. However, Upsilon And itself is visible to the unaided eye shining in Earth's sky in the northern constellation Andromeda [ http://cfa-www.harvard.edu/afoe/And.html ] at about 4th magnitude [ http://liftoff.msfc.nasa.gov/academy/universe/MAG.HTML ]. This deep photographic image [ http://aibn47.astro.uni-bonn.de/~gallery/constellations/ andromeda/constell.html ] shows Upsilon And along with fainter stars and "deep sky" objects including the famous Andromeda spiral galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap971101.html ] or M31 (right), the Triangulum galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap980721.html ] or M33 (below), and the star cluster NGC 752 [ http://www.seds.org/messier/xtra/ngc/n0752.html ] (left). About 44 light-years distant, Upsilon And is a star only a little more massive and just slightly hotter than the Sun. |
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Upsilon Andromedae: An Extra
…
| Title |
Upsilon Andromedae: An Extra-Solar System |
| Explanation |
Yesterday, astronomers announced [ http://cfa-www.harvard.edu/afoe/upsAnd_pr.html ] the discovery of the first system of planets around a normal star other than our Sun [ http://www.seds.org/nineplanets/nineplanets/sol.html ]. Previously, only single planet star systems [ http://www.physics.sfsu.edu/~gmarcy/planetsearch/ ] had been found. Subtle changes in the wobble of Upsilon Andromedae [ http://www.physics.sfsu.edu/~gmarcy/planetsearch/upsand/upsand.html ], a Sun-like star in the constellation [ http://www.astro.wisc.edu/~dolan/constellations/extra/constellations.html ] of Andromeda [ http://www.astro.wisc.edu/~dolan/constellations/constellations/Andromeda.html ], allowed astronomers led by R. Paul Butler [ http://astro.berkeley.edu/~paul/vita.html ] (AAO [ http://www.aao.gov.au/aaohomepage.html ]) and Geoffrey W. Marcy [ http://cannon.sfsu.edu/~gmarcy/ ] (SFSU [ http://cannon.sfsu.edu/ ] /UCB [ http://astron.berkeley.edu/home.html ]) to make the breakthrough. This star system is quite different from our own Solar System [ http://antwrp.gsfc.nasa.gov/apod/ap980517.html ], however. All three detected planets have masses near or above Jupiter [ http://www.seds.org/nineplanets/nineplanets/jupiter.html ]. The discovery [ http://science.nasa.gov/newhome/headlines/ast15apr99_1.htm ] implies that multiple-planet systems [ http://antwrp.gsfc.nasa.gov/apod/ap961019.html ] are quite common, increasing speculation that life-bearing [ http://cmex-www.arc.nasa.gov/VikingCD/Puzzle/EvoLife.htm ] planets similar to Earth [ http://antwrp.gsfc.nasa.gov/apod/ap990131.html ] may one day be found. The drawing above is an artist's depiction of the Upsilon Andromedae [ http://antwrp.gsfc.nasa.gov/apod/ap990416.html http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1997ApJ...474L.119B ] system and its innermost planet. This planet orbits unexpectedly close to its parent star. |
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