Very, very interesting. Never heard of PAH referred to in the optical, and was not aware that it was the source of extended red emission.
Thanks.
Full Version: NASA Astronomy Picture of the Day
Astronomy Picture of the Day
2008 January 12
Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Discover the Cosmos !
Mercury Chases the Sunset
Image Credit & Copyright: Doug Zubenel
Explanation: This colorful view of the western sky at sunset features last Wednesday's slender crescent Moon. Of course, when the Moon is in its crescent phase it can never be far from the Sun in the sky. Also always close to the Sun in Earth's sky is innermost planet Mercury, seen here below and right of center against the bright orange glow along the horizon. Mercury is usually difficult to glimpse because of overwhelming sunlight, but increasingly better views of the small planet after sunset will be possible as it wanders farther east of the Sun in the coming days. On January 14th, NASA's MESSENGER spacecraft will have a good view too, as it makes its first Mercury flyby.
Tomorrow's picture: from above
2008 January 12
Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Discover the Cosmos !
Mercury Chases the Sunset
Image Credit & Copyright: Doug Zubenel
Explanation: This colorful view of the western sky at sunset features last Wednesday's slender crescent Moon. Of course, when the Moon is in its crescent phase it can never be far from the Sun in the sky. Also always close to the Sun in Earth's sky is innermost planet Mercury, seen here below and right of center against the bright orange glow along the horizon. Mercury is usually difficult to glimpse because of overwhelming sunlight, but increasingly better views of the small planet after sunset will be possible as it wanders farther east of the Sun in the coming days. On January 14th, NASA's MESSENGER spacecraft will have a good view too, as it makes its first Mercury flyby.
Tomorrow's picture: from above
These photos are awesome! I have alway been in wonder of our universe! Thanks for sharing!
Astronomy Picture of The Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 January 13
Hurricane Ivan from the Space Station
Credit: Expedition 9 Crew, International Space Station, NASA
Explanation: Ninety percent of the houses on Grenada were damaged by the destructive force of Hurricane Ivan. At its peak, Ivan was a Category 5 hurricane, the highest power category on the Saffir-Simpson Scale, and created sustained winds in excess of 200 kilometers per hour. Ivan was the largest hurricane to strike the US in 2004, and, so far, the 10th most powerful in recorded history. As it swirled in the Atlantic Ocean, the tremendous eye of Hurricane Ivan was photographed from above by the orbiting International Space Station. The name Ivan has now been retired from Atlantic Ocean use by the World Meteorological Organization.
Note: Astronomy lectures by an APOD editor are now available as a free podcast.
Tomorrow's picture: colorful cocoon
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 January 13
Hurricane Ivan from the Space Station
Credit: Expedition 9 Crew, International Space Station, NASA
Explanation: Ninety percent of the houses on Grenada were damaged by the destructive force of Hurricane Ivan. At its peak, Ivan was a Category 5 hurricane, the highest power category on the Saffir-Simpson Scale, and created sustained winds in excess of 200 kilometers per hour. Ivan was the largest hurricane to strike the US in 2004, and, so far, the 10th most powerful in recorded history. As it swirled in the Atlantic Ocean, the tremendous eye of Hurricane Ivan was photographed from above by the orbiting International Space Station. The name Ivan has now been retired from Atlantic Ocean use by the World Meteorological Organization.
Note: Astronomy lectures by an APOD editor are now available as a free podcast.
Tomorrow's picture: colorful cocoon
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 January 14
The Cocoon Nebula from CFHT
Credit & Copyright: Jean-Charles Cuillandre (CFHT), Hawaiian Starlight, CFHT
Explanation: What creates the colors of the Cocoon Nebula? The Cocoon Nebula, cataloged as IC 5146, is a strikingly beautiful nebula located about 4,000 light years away toward the constellation of the Swan (Cygnus). Inside the Cocoon Nebula is a newly developing open cluster of stars. Like other stellar nurseries, the Cocoon Nebula holds, at the same time, a bright red emission nebula, blue reflection nebulas, and dark absorption nebulas. Given different mixtures, these three processes create a host of colors in this image taken recently by the Canada-France-Hawaii Telescope (CFHT) in Hawaii, USA. Speculation based on recent measurements holds that the massive star towards the left of the picture opened a hole in an existing molecular cloud through which much of the glowing material flows. The same star, which formed about 100,000 years ago, now provides the energy source for much of the emitted and reflected light from this nebula.
Tomorrow's picture: open space
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 January 14
The Cocoon Nebula from CFHT
Credit & Copyright: Jean-Charles Cuillandre (CFHT), Hawaiian Starlight, CFHT
Explanation: What creates the colors of the Cocoon Nebula? The Cocoon Nebula, cataloged as IC 5146, is a strikingly beautiful nebula located about 4,000 light years away toward the constellation of the Swan (Cygnus). Inside the Cocoon Nebula is a newly developing open cluster of stars. Like other stellar nurseries, the Cocoon Nebula holds, at the same time, a bright red emission nebula, blue reflection nebulas, and dark absorption nebulas. Given different mixtures, these three processes create a host of colors in this image taken recently by the Canada-France-Hawaii Telescope (CFHT) in Hawaii, USA. Speculation based on recent measurements holds that the massive star towards the left of the picture opened a hole in an existing molecular cloud through which much of the glowing material flows. The same star, which formed about 100,000 years ago, now provides the energy source for much of the emitted and reflected light from this nebula.
Tomorrow's picture: open space
Discover the Cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 January 25
Winter Night at Pic du Midi
Credit & Copyright: Alain Sallez (picdumidi.org), David Romeuf (Université Lyon 1)
Explanation: This dreamlike view looking south from the historic mountain top Pic du Midi Observatory combines moonlit domes, a winter night sky, and the snowy peaks of the French Pyrenees. Encroaching on the night, lights from the La Mongie ski resort illuminate the mountain slopes nearby while the glow along the distant horizon is from urban areas in southern France and Spain. The night sky features stars of the constellations Orion and Gemini with a bright planet Mars very near the top edge, left of center. The three prominent domes visible (from left to right) house a 0.6 meter telescope reserved for amateur astronomers, a 1 meter telescope that was used to support the Apollo lunar landing missions, and the new, Sun-watching CLIMSO.
Tomorrow's picture: Mercury in Color
IC 2948: The Running Chicken Nebula
Explanation: Bright nebulae abound in and around the expansive southern constellation of Centaurus. This one, cataloged as IC 2948 is near the star Lambda Centauri and not far on the sky from the better known Eta Carinae Nebula. Embedded in the reddish glowing cloud of hydrogen gas, typical of emission nebulae found in massive star-forming regions, is the energetic young star cluster IC 2944. Seen in silhouette near the top of the view are small, dark clouds of obscuring cosmic dust. Called Thackeray's Globules for their discoverer, they are potential sites for the formation of new stars, but are likely being eroded by the intense radiation from the nearby young stars. Of course, gazing at the center of the region suggests to some IC 2948's popular name - The Running Chicken Nebula. The gorgeous skyscape spans about 70 light-years at the nebula's estimated 6,000 light-year distance.
Astronomy Picture of the Day
I can't see the running chicken..
Explanation: Bright nebulae abound in and around the expansive southern constellation of Centaurus. This one, cataloged as IC 2948 is near the star Lambda Centauri and not far on the sky from the better known Eta Carinae Nebula. Embedded in the reddish glowing cloud of hydrogen gas, typical of emission nebulae found in massive star-forming regions, is the energetic young star cluster IC 2944. Seen in silhouette near the top of the view are small, dark clouds of obscuring cosmic dust. Called Thackeray's Globules for their discoverer, they are potential sites for the formation of new stars, but are likely being eroded by the intense radiation from the nearby young stars. Of course, gazing at the center of the region suggests to some IC 2948's popular name - The Running Chicken Nebula. The gorgeous skyscape spans about 70 light-years at the nebula's estimated 6,000 light-year distance.
Astronomy Picture of the Day
I can't see the running chicken..
QUOTE (Ghost Ship @ Apr 18 2008, 03:36 PM) 
I can't see the running chicken..
It's the entire nebula. Top-right corner looks like a beak, the middle looks like wings spreading as if it were running. Also, near the top-middle the dark-spot that blends in with two stars looks like a spaceship firing its engines.
Merging the two posts above with the existing "Astronomy Picture of the Day" thread.
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 April 20
Spiral Galaxies in Collision
Credit: Debra Meloy Elmegreen (Vassar College) et al.,
& the Hubble Heritage Team (AURA/STScI/NASA)
Explanation: Billions of years from now, only one of these two galaxies will remain. Until then, spiral galaxies NGC 2207 and IC 2163 will slowly pull each other apart, creating tides of matter, sheets of shocked gas, lanes of dark dust, bursts of star formation, and streams of cast-away stars. Astronomers predict that NGC 2207, the larger galaxy on the left, will eventually incorporate IC 2163, the smaller galaxy on the right. In the most recent encounter that peaked 40 million years ago, the smaller galaxy is swinging around counter-clockwise, and is now slightly behind the larger galaxy. The space between stars is so vast that when galaxies collide, the stars in them usually do not collide.
Astronomy picture of the day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 April 20
Spiral Galaxies in Collision
Credit: Debra Meloy Elmegreen (Vassar College) et al.,
& the Hubble Heritage Team (AURA/STScI/NASA)
Explanation: Billions of years from now, only one of these two galaxies will remain. Until then, spiral galaxies NGC 2207 and IC 2163 will slowly pull each other apart, creating tides of matter, sheets of shocked gas, lanes of dark dust, bursts of star formation, and streams of cast-away stars. Astronomers predict that NGC 2207, the larger galaxy on the left, will eventually incorporate IC 2163, the smaller galaxy on the right. In the most recent encounter that peaked 40 million years ago, the smaller galaxy is swinging around counter-clockwise, and is now slightly behind the larger galaxy. The space between stars is so vast that when galaxies collide, the stars in them usually do not collide.
Astronomy picture of the day
QUOTE (Roughneck @ Apr 18 2008, 03:38 PM)
It's the entire nebula. Top-right corner looks like a beak, the middle looks like wings spreading as if it were running. Also, near the top-middle the dark-spot that blends in with two stars looks like a spaceship firing its engines.
ah, i see it now. Thanks.
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Bacteriophages: The Most Common Life-Like Form on Earth
Credit: Wikipedia; Insert: Mike Jones
Explanation: There are more bacteriophages on Earth than any other life-like form. These small viruses are not clearly a form of life, since when not attached to bacteria they are completely dormant. Bacteriophages attack and eat bacteria and have likely been doing so for over 3 billion years ago. Although initially discovered early last century, the tremendous abundance of phages was realized more recently when it was found that a single drop of common seawater typically contains millions of them. Extrapolating, phages are likely to be at least a billion billion (sic) times more numerous than humans. Pictured above is an electron micrograph of over a dozen bacteriophages attached to a single bacterium. Phages are very small -- it would take about a million of them laid end-to-end to span even one millimeter. The ability to kill bacteria makes phages a potential ally against bacteria that cause human disease, although bacteriophages are not yet well enough understood to be in wide spread medical use.
Tomorrow's picture: blue fox
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Bacteriophages: The Most Common Life-Like Form on Earth
Credit: Wikipedia; Insert: Mike Jones
Explanation: There are more bacteriophages on Earth than any other life-like form. These small viruses are not clearly a form of life, since when not attached to bacteria they are completely dormant. Bacteriophages attack and eat bacteria and have likely been doing so for over 3 billion years ago. Although initially discovered early last century, the tremendous abundance of phages was realized more recently when it was found that a single drop of common seawater typically contains millions of them. Extrapolating, phages are likely to be at least a billion billion (sic) times more numerous than humans. Pictured above is an electron micrograph of over a dozen bacteriophages attached to a single bacterium. Phages are very small -- it would take about a million of them laid end-to-end to span even one millimeter. The ability to kill bacteria makes phages a potential ally against bacteria that cause human disease, although bacteriophages are not yet well enough understood to be in wide spread medical use.
Tomorrow's picture: blue fox
Keep-em-comeing this is how we can get everyone to get the knowledge bug.
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 April 23
Above the Clouds
Credit & Copyright: Serge Brunier (TWAN)
Explanation: From the windswept peak of Mauna Kea, on the Big Island of Hawaii, your view of the world at night could look like this. At an altitude of about 13,500 feet, the mountain top is silhouetted in the stunning skyscape recorded near dusk in early December of 2005. The volcanic peak rises just above a sea of storm clouds illuminated by a bright Moon. Planet Venus is setting near the Moon as the brilliant evening star. The scene also includes the faint, milky band of our own galaxy's disk of stars and cosmic dust clouds stretching from the horizon into the sky along the right edge of the frame.
Tomorrow's picture: stars or no stars
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 April 23
Above the Clouds
Credit & Copyright: Serge Brunier (TWAN)
Explanation: From the windswept peak of Mauna Kea, on the Big Island of Hawaii, your view of the world at night could look like this. At an altitude of about 13,500 feet, the mountain top is silhouetted in the stunning skyscape recorded near dusk in early December of 2005. The volcanic peak rises just above a sea of storm clouds illuminated by a bright Moon. Planet Venus is setting near the Moon as the brilliant evening star. The scene also includes the faint, milky band of our own galaxy's disk of stars and cosmic dust clouds stretching from the horizon into the sky along the right edge of the frame.
Tomorrow's picture: stars or no stars
Astronomy Picture of the Day
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 April 24
Cygnus Without Stars
Credit & Copyright: Igor Chekalin
Explanation: The sky is full of hydrogen, though it can take a sensitive camera and telescope to see it. For example, this twelve-degree-wide view of the northern part of the constellation Cygnus reveals cosmic clouds of hydrogen gas along the plane of our Milky Way galaxy. The mosaic of telescopic images was recorded through an h-alpha filter that transmits only visible red light from glowing hydrogen atoms. Further digital processing has removed most of what is left of the myriad, point-like Milky Way stars from the scene, though bright Deneb, alpha star of Cygnus and head of the Northern Cross, remains near top center. Recognizable bright nebulae include NGC 7000 (North America Nebula), and IC 5070 (Pelican Nebula) at the upper left with IC 1318 (Butterfly Nebula) and NGC 6888 (Crescent Nebula) at lower right -- but others can be found throughout the wide field. Want the stars back? Just slide your cursor over the picture.
Tomorrow's picture: M86 and friends
stronomy Picture of Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 April 24
Cygnus Without Stars
Credit & Copyright: Igor Chekalin
Explanation: The sky is full of hydrogen, though it can take a sensitive camera and telescope to see it. For example, this twelve-degree-wide view of the northern part of the constellation Cygnus reveals cosmic clouds of hydrogen gas along the plane of our Milky Way galaxy. The mosaic of telescopic images was recorded through an h-alpha filter that transmits only visible red light from glowing hydrogen atoms. Further digital processing has removed most of what is left of the myriad, point-like Milky Way stars from the scene, though bright Deneb, alpha star of Cygnus and head of the Northern Cross, remains near top center. Recognizable bright nebulae include NGC 7000 (North America Nebula), and IC 5070 (Pelican Nebula) at the upper left with IC 1318 (Butterfly Nebula) and NGC 6888 (Crescent Nebula) at lower right -- but others can be found throughout the wide field. Want the stars back? Just slide your cursor over the picture.
Tomorrow's picture: M86 and friends
stronomy Picture of Day
219208main_s123e008274_full.jpg
I aint' ever got no luck with images, you know me...
but, the one listed is a cover-up. Yes, it is...
If you download the full resolution photo, and go through magnification, you see lunar exposure. Out of focal ranges galore. This is their response to the media amused at their clatter-chatter they heard on communications. And, they kept saying it was debris, causing concern. Something, up there, was buzzing. And, I don't think among the literal millions of pieces of space junk, screams are iterated like they were:
But, you know, I'll give 'em a credit. At least in the copy-paste ritual, they chose "cut" of the original region...kudos...
I aint' ever got no luck with images, you know me...
but, the one listed is a cover-up. Yes, it is...
If you download the full resolution photo, and go through magnification, you see lunar exposure. Out of focal ranges galore. This is their response to the media amused at their clatter-chatter they heard on communications. And, they kept saying it was debris, causing concern. Something, up there, was buzzing. And, I don't think among the literal millions of pieces of space junk, screams are iterated like they were:
But, you know, I'll give 'em a credit. At least in the copy-paste ritual, they chose "cut" of the original region...kudos...
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 April 25
M86 in the Virgo Cluster
Credit & Copyright: Greg Morgan (Sierra Remote Observatories)
Explanation: Bright lenticular galaxy M86 is near center of this cosmic view, at the heart of the Virgo Galaxy Cluster. Other bright galaxies in the neighborhood include M84 at the upper right, edge-on spiral NGC4388 near the right edge, a striking pair of interacting galaxies, Markarian's Eyes, in the lower left corner, and edge-on spiral NGC 4402 at about 11 o'clock. With well over a thousand members, the Virgo Cluster is the closest large cluster of galaxies. On average the cluster galaxies are measured to be about 50 million light-years away. The entire Virgo Cluster is difficult to appreciate because it covers such a large area, spanning over 10 degrees on the sky. This cluster close-up covers a region just under 1 degree wide or about 1.5 times the size of the full moon.
Tomorrow's picture: the zone
Astronomy Picture of Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 April 25
M86 in the Virgo Cluster
Credit & Copyright: Greg Morgan (Sierra Remote Observatories)
Explanation: Bright lenticular galaxy M86 is near center of this cosmic view, at the heart of the Virgo Galaxy Cluster. Other bright galaxies in the neighborhood include M84 at the upper right, edge-on spiral NGC4388 near the right edge, a striking pair of interacting galaxies, Markarian's Eyes, in the lower left corner, and edge-on spiral NGC 4402 at about 11 o'clock. With well over a thousand members, the Virgo Cluster is the closest large cluster of galaxies. On average the cluster galaxies are measured to be about 50 million light-years away. The entire Virgo Cluster is difficult to appreciate because it covers such a large area, spanning over 10 degrees on the sky. This cluster close-up covers a region just under 1 degree wide or about 1.5 times the size of the full moon.
Tomorrow's picture: the zone
Astronomy Picture of Day
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 April 26
The Tarantula Zone
Credit & Copyright: Robert Gendler
Explanation: The Tarantula Nebula is more than 1,000 light-years in diameter -- a giant star forming region within our neighboring galaxy the Large Magellanic Cloud (LMC). That cosmic arachnid lies at the upper left of this expansive mosiac covering a part of the LMC over 6,000 light-years across. Within the Tarantula (NGC 2070), intense radiation, stellar winds and supernova shocks from the central young cluster of massive stars, cataloged as R136, energize the nebular glow and shape the spidery filaments. Around the Tarantula are other violent star-forming regions with young star clusters, filaments and bubble-shaped clouds. The small but expanding remnant of supernova 1987a, the closest supernova in modern history, is located near the center of the view. The rich field is about as wide as four full moons on the sky, located in the southern constellation Dorado.
Tomorrow's picture: on the radio
Astronomy Picture of Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 April 26
The Tarantula Zone
Credit & Copyright: Robert Gendler
Explanation: The Tarantula Nebula is more than 1,000 light-years in diameter -- a giant star forming region within our neighboring galaxy the Large Magellanic Cloud (LMC). That cosmic arachnid lies at the upper left of this expansive mosiac covering a part of the LMC over 6,000 light-years across. Within the Tarantula (NGC 2070), intense radiation, stellar winds and supernova shocks from the central young cluster of massive stars, cataloged as R136, energize the nebular glow and shape the spidery filaments. Around the Tarantula are other violent star-forming regions with young star clusters, filaments and bubble-shaped clouds. The small but expanding remnant of supernova 1987a, the closest supernova in modern history, is located near the center of the view. The rich field is about as wide as four full moons on the sky, located in the southern constellation Dorado.
Tomorrow's picture: on the radio
Astronomy Picture of Day
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 April 27
The Galactic Center Radio Arc
Credit: Farhad Zadeh et al. (Northwestern), VLA, NRAO
Explanation: What causes this unusual structure near the center of our Galaxy? The long parallel rays slanting across the top of the above radio image are known collectively as the Galactic Center Radio Arc and jut straight out from the Galactic plane. The Radio Arc is connected to the Galactic center by strange curving filaments known as the Arches. The bright radio structure at the bottom right likely surrounds a black hole at the Galactic center and is known as Sagittarius A*. One origin hypothesis holds that the Radio Arc and the Arches have their geometry because they contain hot plasma flowing along lines of constant magnetic field. Images from the Chandra X-ray Observatory appear to show this plasma colliding with a nearby cloud of cold gas.
Tomorrow's picture: bright steps
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 April 27
The Galactic Center Radio Arc
Credit: Farhad Zadeh et al. (Northwestern), VLA, NRAO
Explanation: What causes this unusual structure near the center of our Galaxy? The long parallel rays slanting across the top of the above radio image are known collectively as the Galactic Center Radio Arc and jut straight out from the Galactic plane. The Radio Arc is connected to the Galactic center by strange curving filaments known as the Arches. The bright radio structure at the bottom right likely surrounds a black hole at the Galactic center and is known as Sagittarius A*. One origin hypothesis holds that the Radio Arc and the Arches have their geometry because they contain hot plasma flowing along lines of constant magnetic field. Images from the Chandra X-ray Observatory appear to show this plasma colliding with a nearby cloud of cold gas.
Tomorrow's picture: bright steps
Astronomy Picture of the Day
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 May 1
The Giants of Omega Centauri
Credit: NASA, JPL-Caltech, Martha Boyer (Univ. Minnesota), et al.
Explanation: Globular star cluster Omega Centauri is some 15,000 light-years away and 150 light-years in diameter. Packed with about 10 million stars, Omega Cen is the largest of 200 or so known globular clusters that roam the halo of our Milky Way galaxy. This intriguing color picture combines a visible light image of the cluster in blue hues with infrared image data from the Spitzer Space Telescope. The Spitzer data includes images in two infrared bands, one shown in green and one in red. Both infrared bands are sensitive to light from the cool, giant stars in the cluster. Adding the red and green colors together creates yellow, showing off the cluster's giant stars as yellow spots. Of course, red spots also indicate cool, giant stars in the image, but some of the red spots are even more distant background galaxies. Also known simply as Red Giant Stars, they represent a stage in the life-cycle of stars more evolved than our own Sun, a stage the Sun will reach in about 5 billion years. Dust grains formed in the atmospheres of cool, giant stars are ultimately involved in the formation of other stars and planets.
Tomorrow's picture: pixels in space
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 May 1
The Giants of Omega Centauri
Credit: NASA, JPL-Caltech, Martha Boyer (Univ. Minnesota), et al.
Explanation: Globular star cluster Omega Centauri is some 15,000 light-years away and 150 light-years in diameter. Packed with about 10 million stars, Omega Cen is the largest of 200 or so known globular clusters that roam the halo of our Milky Way galaxy. This intriguing color picture combines a visible light image of the cluster in blue hues with infrared image data from the Spitzer Space Telescope. The Spitzer data includes images in two infrared bands, one shown in green and one in red. Both infrared bands are sensitive to light from the cool, giant stars in the cluster. Adding the red and green colors together creates yellow, showing off the cluster's giant stars as yellow spots. Of course, red spots also indicate cool, giant stars in the image, but some of the red spots are even more distant background galaxies. Also known simply as Red Giant Stars, they represent a stage in the life-cycle of stars more evolved than our own Sun, a stage the Sun will reach in about 5 billion years. Dust grains formed in the atmospheres of cool, giant stars are ultimately involved in the formation of other stars and planets.
Tomorrow's picture: pixels in space
Astronomy Picture of the Day
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 May 2
Shaping NGC 6188
Credit & Copyright: John Ebersole
Explanation: Dark shapes with bright edges winging their way through dusty NGC 6188 are tens of light-years long. The emission nebula is found near the edge of an otherwise dark large molecular cloud in the southern constellation Ara, about 4,000 light-years away. Formed in that region only a few million years ago, the massive young stars of the embedded Ara OB1 association sculpt the fantastic shapes and power the nebular glow with stellar winds and intense ultraviolet radiation. The recent star formation itself was likely triggered by winds and supernova explosions, from previous generations of massive stars, that swept up and compressed the molecular gas. A false-color Hubble palette was used to create the this gorgeous wide-field image and shows emission from sulfur, hydrogen, and oxygen atoms in red, green, and blue hues. At the estimated distance of NGC 6188, the picture spans about 300 light-years.
Tomorrow's picture: milky way pan
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 May 2
Shaping NGC 6188
Credit & Copyright: John Ebersole
Explanation: Dark shapes with bright edges winging their way through dusty NGC 6188 are tens of light-years long. The emission nebula is found near the edge of an otherwise dark large molecular cloud in the southern constellation Ara, about 4,000 light-years away. Formed in that region only a few million years ago, the massive young stars of the embedded Ara OB1 association sculpt the fantastic shapes and power the nebular glow with stellar winds and intense ultraviolet radiation. The recent star formation itself was likely triggered by winds and supernova explosions, from previous generations of massive stars, that swept up and compressed the molecular gas. A false-color Hubble palette was used to create the this gorgeous wide-field image and shows emission from sulfur, hydrogen, and oxygen atoms in red, green, and blue hues. At the estimated distance of NGC 6188, the picture spans about 300 light-years.
Tomorrow's picture: milky way pan
Astronomy Picture of the Day
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 May 3
Alborz Mountain Miky Way
Credit & Copyright: Babak Tafreshi (TWAN)
Explanation: Snow-capped stratovolcano Mt. Damavand climbs to 5,670 meters (18,598 feet) near the left edge in this panoramic view of the world at night. In the sky to the left of Damavand's peak are the stars of the Big Dipper in Ursa Major. Pan to the right and your gaze will sweep across the arch of our Milky Way Galaxy above the Alborz Mountain Range bordering the Caspian Sea. Near the center of the panorama, recorded in the predawn hours of April 4th, bright stars Deneb and Altair lie close to the curve of the Milky Way, above the glow of the Haraz valley. Farther right, brilliant Jupiter dominates the sky near the stars, nebulae, and dark dust clouds toward the bulging galactic center. Finally, the horizon glow at the right edge, below bright yellowish giant star Antares, is from the city of Damavand, named for the legendary mountain peak.
Tomorrow's picture: antarctic eclipse
Astronomy Picture of Day
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2008 May 3
Alborz Mountain Miky Way
Credit & Copyright: Babak Tafreshi (TWAN)
Explanation: Snow-capped stratovolcano Mt. Damavand climbs to 5,670 meters (18,598 feet) near the left edge in this panoramic view of the world at night. In the sky to the left of Damavand's peak are the stars of the Big Dipper in Ursa Major. Pan to the right and your gaze will sweep across the arch of our Milky Way Galaxy above the Alborz Mountain Range bordering the Caspian Sea. Near the center of the panorama, recorded in the predawn hours of April 4th, bright stars Deneb and Altair lie close to the curve of the Milky Way, above the glow of the Haraz valley. Farther right, brilliant Jupiter dominates the sky near the stars, nebulae, and dark dust clouds toward the bulging galactic center. Finally, the horizon glow at the right edge, below bright yellowish giant star Antares, is from the city of Damavand, named for the legendary mountain peak.
Tomorrow's picture: antarctic eclipse
Astronomy Picture of Day
Astronomy Picture of the Day
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2008 May 4
An Antarctic Total Solar Eclipse
Credit and Copyright: Fred Bruenjes (moonglow.net)
Explanation: The Sun, the Moon, Antarctica, and two photographers all lined up in 2003 Antarctica during an unusual total eclipse of the Sun. Even given the extreme location, a group of enthusiastic eclipse chasers ventured near the bottom of the world to experience the surreal momentary disappearance of the Sun behind the Moon. One of the treasures collected was the above picture -- a composite of four separate images digitally combined to realistically simulate how the adaptive human eye saw the eclipse. As the image was taken, both the Moon and the Sun peaked together over an Antarctic ridge. In the sudden darkness, the magnificent corona of the Sun became visible around the Moon. Quite by accident, another photographer was caught in one of the images checking his video camera. Visible to his left are an equipment bag and a collapsible chair.
Tomorrow's picture: saturn electric
Astronomy Picture of the Day
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2008 May 4
An Antarctic Total Solar Eclipse
Credit and Copyright: Fred Bruenjes (moonglow.net)
Explanation: The Sun, the Moon, Antarctica, and two photographers all lined up in 2003 Antarctica during an unusual total eclipse of the Sun. Even given the extreme location, a group of enthusiastic eclipse chasers ventured near the bottom of the world to experience the surreal momentary disappearance of the Sun behind the Moon. One of the treasures collected was the above picture -- a composite of four separate images digitally combined to realistically simulate how the adaptive human eye saw the eclipse. As the image was taken, both the Moon and the Sun peaked together over an Antarctic ridge. In the sudden darkness, the magnificent corona of the Sun became visible around the Moon. Quite by accident, another photographer was caught in one of the images checking his video camera. Visible to his left are an equipment bag and a collapsible chair.
Tomorrow's picture: saturn electric
Astronomy Picture of the Day
Astronomy Picture of the Day
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2008 May 5
A Persistent Electrical Storm on Saturn
Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA
Explanation: How do large storms evolve on Saturn? On Earth, a hurricane can persist for weeks, while the Great Red Spot on Jupiter has been in existence for over 150 years. On Saturn, a storm system has now set a new endurance record, now being discernable for greater than three months. Electrical signals were detected from the storm in late November of 2007, while the above image was taken in early March 2008. The storm has roughly the width of planet Earth. Planetary scientists hypothesize that the storm runs deep into Saturn's cloud tops. The above image is shown in exaggerated colors combining violet and green light with light normally too red for humans to see. Visible on the upper right are shadows of Saturn's expansive ring system. Careful inspection will reveal Saturn's small moon Janus just below a ring shadow. Understanding weather on other planets helps atmospheric scientists better understand our Earth's weather. Observers of our Solar System's huge ringed world will be tracking the storm to see how it evolves and how long it will ultimately last.
Tomorrow's picture: open space
Astronomy Picture of Day
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2008 May 5
A Persistent Electrical Storm on Saturn
Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA
Explanation: How do large storms evolve on Saturn? On Earth, a hurricane can persist for weeks, while the Great Red Spot on Jupiter has been in existence for over 150 years. On Saturn, a storm system has now set a new endurance record, now being discernable for greater than three months. Electrical signals were detected from the storm in late November of 2007, while the above image was taken in early March 2008. The storm has roughly the width of planet Earth. Planetary scientists hypothesize that the storm runs deep into Saturn's cloud tops. The above image is shown in exaggerated colors combining violet and green light with light normally too red for humans to see. Visible on the upper right are shadows of Saturn's expansive ring system. Careful inspection will reveal Saturn's small moon Janus just below a ring shadow. Understanding weather on other planets helps atmospheric scientists better understand our Earth's weather. Observers of our Solar System's huge ringed world will be tracking the storm to see how it evolves and how long it will ultimately last.
Tomorrow's picture: open space
Astronomy Picture of Day
Fascinating pictures Ghost Ship.Now I now where I can get new desktop backgrounds. 
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 May 6
Galaxies Collide in NGC 3256
Credit: NASA, ESA, Hubble Heritage (STScI / AURA) - ESA/Hubble Collaboration, & A. Evans (UVa, NRAO, SUNYSB)
Explanation: Galaxies don't normally look like this. NGC 3256 actually shows a current picture of two galaxies that are slowly colliding. Quite possibly, in hundreds of millions of years, only one galaxy will remain. Today, however, NGC 3256 shows intricate filaments of dark dust, unusual tidal tails of stars, and a peculiar center that contains two distinct nuclei. Although it is likely that no stars in the two galaxies will directly collide, the gas, dust, and ambient magnetic fields do interact directly. NGC 3256, part of the vast Hydra-Centaurus supercluster of galaxies, spans over 100 thousand light-years across and is located about 100 million light-years away.
Tomorrow's picture: the gegenschein
astronomy picture of the day
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2008 May 6
Galaxies Collide in NGC 3256
Credit: NASA, ESA, Hubble Heritage (STScI / AURA) - ESA/Hubble Collaboration, & A. Evans (UVa, NRAO, SUNYSB)
Explanation: Galaxies don't normally look like this. NGC 3256 actually shows a current picture of two galaxies that are slowly colliding. Quite possibly, in hundreds of millions of years, only one galaxy will remain. Today, however, NGC 3256 shows intricate filaments of dark dust, unusual tidal tails of stars, and a peculiar center that contains two distinct nuclei. Although it is likely that no stars in the two galaxies will directly collide, the gas, dust, and ambient magnetic fields do interact directly. NGC 3256, part of the vast Hydra-Centaurus supercluster of galaxies, spans over 100 thousand light-years across and is located about 100 million light-years away.
Tomorrow's picture: the gegenschein
astronomy picture of the day
Astronomy Picture of the Day
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2008 May 7
The Gegenschein Over Chile
Credit & Copyright: Yuri Beletsky (ESO)
Explanation: Is the night sky darkest in the direction opposite the Sun? No. In fact, a rarely discernable faint glow known as the gegenschein (German for "counter glow") can be seen 180 degrees around from the Sun in an extremely dark sky. The gegenschein is sunlight back-scattered off small interplanetary dust particles. These dust particles are millimeter sized splinters from asteroids and orbit in the ecliptic plane of the planets. Pictured above from last October is one of the most spectacular pictures of the gegenschein yet taken. Here a deep exposure of an extremely dark sky over Paranal Observatory in Chile shows the gegenschein so clearly that even a surrounding glow is visible. In the foreground are several of the European Southern Observatory's Very Large Telescopes, while notable background objects include the Andromeda galaxy toward the lower left and the Pleiades star cluster just above the horizon. The gegenschein is distinguished from zodiacal light near the Sun by the high angle of reflection. During the day, a phenomenon similar to the gegenschein called the glory can be seen in reflecting air or clouds opposite the Sun from an airplane.
Tomorrow's picture: to the Dark Tower
Astronomy picture of the day
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2008 May 7
The Gegenschein Over Chile
Credit & Copyright: Yuri Beletsky (ESO)
Explanation: Is the night sky darkest in the direction opposite the Sun? No. In fact, a rarely discernable faint glow known as the gegenschein (German for "counter glow") can be seen 180 degrees around from the Sun in an extremely dark sky. The gegenschein is sunlight back-scattered off small interplanetary dust particles. These dust particles are millimeter sized splinters from asteroids and orbit in the ecliptic plane of the planets. Pictured above from last October is one of the most spectacular pictures of the gegenschein yet taken. Here a deep exposure of an extremely dark sky over Paranal Observatory in Chile shows the gegenschein so clearly that even a surrounding glow is visible. In the foreground are several of the European Southern Observatory's Very Large Telescopes, while notable background objects include the Andromeda galaxy toward the lower left and the Pleiades star cluster just above the horizon. The gegenschein is distinguished from zodiacal light near the Sun by the high angle of reflection. During the day, a phenomenon similar to the gegenschein called the glory can be seen in reflecting air or clouds opposite the Sun from an airplane.
Tomorrow's picture: to the Dark Tower
Astronomy picture of the day
Astronomy Picture of the Day
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2008 May 8
The Dark Tower in Scorpius
Credit & Copyright: Robert Gendler
Explanation: In silhouette against a crowded star field toward the constellation Scorpius, this dusty cosmic cloud evokes for some the image of an ominous dark tower. In fact, clumps of dust and molecular gas collapsing to form stars may well lurk within the dark nebula, a structure that spans almost 40 light-years across the gorgeous telescopic view. Known as a cometary globule, the swept-back cloud, extending from the upper right to the head (top of the tower) left and below center, is shaped by intense ultraviolet radiation from the OB association of very hot stars in NGC 6231, off the left edge of the scene. That energetic ultraviolet light also powers the globule's bordering reddish glow of hydrogen gas. Hot stars embedded in the dust can be seen as small bluish reflection nebulae. This dark tower, NGC 6231, and associated nebulae are about 5,000 light-years away.
Tomorrow's picture: when Moon meets Mercury
Astronomy Picture of the day
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2008 May 8
The Dark Tower in Scorpius
Credit & Copyright: Robert Gendler
Explanation: In silhouette against a crowded star field toward the constellation Scorpius, this dusty cosmic cloud evokes for some the image of an ominous dark tower. In fact, clumps of dust and molecular gas collapsing to form stars may well lurk within the dark nebula, a structure that spans almost 40 light-years across the gorgeous telescopic view. Known as a cometary globule, the swept-back cloud, extending from the upper right to the head (top of the tower) left and below center, is shaped by intense ultraviolet radiation from the OB association of very hot stars in NGC 6231, off the left edge of the scene. That energetic ultraviolet light also powers the globule's bordering reddish glow of hydrogen gas. Hot stars embedded in the dust can be seen as small bluish reflection nebulae. This dark tower, NGC 6231, and associated nebulae are about 5,000 light-years away.
Tomorrow's picture: when Moon meets Mercury
Astronomy Picture of the day
Astronomy Picture of the Day
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2008 May 10
Stars and Mars
Credit & Copyright: Doug Zubenel (TWAN)
Explanation: Wandering through the evening sky, on May 4th planet Mars stood in line with Castor and Pollux, the two bright stars of the constellation Gemini. In this time exposure of the celestial alignment, Mars actually takes on a distinct yellowish hue, contrasting in color with Pollux; a giant star known to have a Jupiter-class planet, and Castor; itself a multiple star system. Though in mythology Pollux and Castor are twin brothers, the two stars are physically unrelated and are about 34 and 50 light-years distant respectively. Included in the skyview are Procyon, alpha star of Canis Minor, and famous star cluster M44 also known as the Beehive Cluster. Dust in our own solar system reflecting sunlight creates the faint band of Zodiacal light emerging from the lower right corner of the frame. Just put your cursor over the picture for help with identifications. Of course, bright Mars can still be found in the western evening skies and tonight wanders near the crescent Moon.
Tomorrow's picture: Mars, backwards
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2008 May 10
Stars and Mars
Credit & Copyright: Doug Zubenel (TWAN)
Explanation: Wandering through the evening sky, on May 4th planet Mars stood in line with Castor and Pollux, the two bright stars of the constellation Gemini. In this time exposure of the celestial alignment, Mars actually takes on a distinct yellowish hue, contrasting in color with Pollux; a giant star known to have a Jupiter-class planet, and Castor; itself a multiple star system. Though in mythology Pollux and Castor are twin brothers, the two stars are physically unrelated and are about 34 and 50 light-years distant respectively. Included in the skyview are Procyon, alpha star of Canis Minor, and famous star cluster M44 also known as the Beehive Cluster. Dust in our own solar system reflecting sunlight creates the faint band of Zodiacal light emerging from the lower right corner of the frame. Just put your cursor over the picture for help with identifications. Of course, bright Mars can still be found in the western evening skies and tonight wanders near the crescent Moon.
Tomorrow's picture: Mars, backwards
Astronomy Picture of theDay
Astronomy Picture of the Day
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2008 May 11
Retrograde Mars
Credit & Copyright: Tunç Tezel (TWAN)
Explanation: Why would Mars appear to move backwards? Most of the time, the apparent motion of Mars in Earth's sky is in one direction, slow but steady in front of the far distant stars. About every two years, however, the Earth passes Mars as they orbit around the Sun. During the most recent such pass over the last year, the proximity of Mars made the red planet appear larger and brighter than usual. Also during this time, Mars appeared to move backwards in the sky, a phenomenon called retrograde motion. Pictured above is a series of images digitally stacked so that all of the stars images coincide. Here, Mars appears to trace out a loop in the sky. Near the top of the loop, Earth passed Mars and the retrograde motion was the highest. Retrograde motion can also be seen for other Solar System planets.
Tomorrow's picture: open space
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 May 11
Retrograde Mars
Credit & Copyright: Tunç Tezel (TWAN)
Explanation: Why would Mars appear to move backwards? Most of the time, the apparent motion of Mars in Earth's sky is in one direction, slow but steady in front of the far distant stars. About every two years, however, the Earth passes Mars as they orbit around the Sun. During the most recent such pass over the last year, the proximity of Mars made the red planet appear larger and brighter than usual. Also during this time, Mars appeared to move backwards in the sky, a phenomenon called retrograde motion. Pictured above is a series of images digitally stacked so that all of the stars images coincide. Here, Mars appears to trace out a loop in the sky. Near the top of the loop, Earth passed Mars and the retrograde motion was the highest. Retrograde motion can also be seen for other Solar System planets.
Tomorrow's picture: open space
Astronomy Picture of the Day
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2008 May 12
The M81 Galaxy Group Through the Integrated Flux Nebula
Credit & Copyright: Jordi Gallego
Explanation: Large galaxies and faint nebula highlight this deep image of the M81 Group of galaxies. First and foremost in the above wide-angle 12-hour exposure is the grand design spiral galaxy M81, the largest galaxy visible in the image. M81 is gravitationally interacting with M82 just below it, a big galaxy with an unusual halo of filamentary red-glowing gas. Around the image many other galaxies from the M81 Group of galaxies can be seen. Together with other galaxy congregates including our Local Group of galaxies and the Virgo Cluster of galaxies, the M81 Group is part of the expansive Virgo Supercluster of Galaxies. This whole galaxy menagerie is seen through the faint nebular glow of the Integrated Flux Nebula, a little studied complex of diffuse gas and dust clouds in our Milky Way Galaxy.
Tomorrow's picture: moon of saturn
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2008 May 12
The M81 Galaxy Group Through the Integrated Flux Nebula
Credit & Copyright: Jordi Gallego
Explanation: Large galaxies and faint nebula highlight this deep image of the M81 Group of galaxies. First and foremost in the above wide-angle 12-hour exposure is the grand design spiral galaxy M81, the largest galaxy visible in the image. M81 is gravitationally interacting with M82 just below it, a big galaxy with an unusual halo of filamentary red-glowing gas. Around the image many other galaxies from the M81 Group of galaxies can be seen. Together with other galaxy congregates including our Local Group of galaxies and the Virgo Cluster of galaxies, the M81 Group is part of the expansive Virgo Supercluster of Galaxies. This whole galaxy menagerie is seen through the faint nebular glow of the Integrated Flux Nebula, a little studied complex of diffuse gas and dust clouds in our Milky Way Galaxy.
Tomorrow's picture: moon of saturn
Astronomy Picture of the Day
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2008 May 13
Ancient Craters of Southern Rhea
Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA
Explanation: Saturn's ragged moon Rhea has one of the oldest surfaces known. Estimated as changing little in the past billion years, Rhea shows craters so old they no longer appear round – their edges have become compromised by more recent cratering. Like Earth's Moon, Rhea's rotation is locked on Saturn, and the above image shows part of Rhea's surface that always faces Saturn. Rhea's leading surface is more highly cratered than its trailing surface. Rhea is composed mostly of water-ice but is thought to include about 25 percent rock and metal. The above image was taken by the robot Cassini spacecraft now orbiting Saturn. Cassini swooped past Rhea last month and captured the above image from about 350,000 kilometers away. Rhea spans 1,500 kilometers making it Saturn's second largest moon after Titan. Several surface features on Rhea remain unexplained including large light patches like those seen near the image top.
Tomorrow's picture: approaching spacecraft
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2008 May 13
Ancient Craters of Southern Rhea
Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA
Explanation: Saturn's ragged moon Rhea has one of the oldest surfaces known. Estimated as changing little in the past billion years, Rhea shows craters so old they no longer appear round – their edges have become compromised by more recent cratering. Like Earth's Moon, Rhea's rotation is locked on Saturn, and the above image shows part of Rhea's surface that always faces Saturn. Rhea's leading surface is more highly cratered than its trailing surface. Rhea is composed mostly of water-ice but is thought to include about 25 percent rock and metal. The above image was taken by the robot Cassini spacecraft now orbiting Saturn. Cassini swooped past Rhea last month and captured the above image from about 350,000 kilometers away. Rhea spans 1,500 kilometers making it Saturn's second largest moon after Titan. Several surface features on Rhea remain unexplained including large light patches like those seen near the image top.
Tomorrow's picture: approaching spacecraft
Astronomy Picture of the Day
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2008 May 14
Supply Ship Docks with the International Space Station
Credit: ISS Expedition 16 Crew, NASA
Explanation: Looking out a window of the International Space Station brings breathtaking views. Visible vistas include a vast and colorful Earth, a deep dark sky, and an occasional spaceship sent to visit the station. Visible early last month was a Soyuz TMA-12 spacecraft carrying not only supplies but also three newcomers. The three new astronauts were Expedition 17 commander Sergei Volkov, flight engineer Oleg Kononenko, and spaceflight participant So-yeon Yi. Yi returned to Earth a few days later, while Volkov and Konenenko are scheduled to return in a few months. The docking module pictured above involved the Pirs Docking Compartment. The Expedition 17 crew, including NASA flight engineer Gregory Chamitoff, will carry out repairs on the ISS, explore new methods of living in space, and conduct research in space including the effects of space radiation on vitamin molecules.
Tomorrow's picture: sideways
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 May 14
Supply Ship Docks with the International Space Station
Credit: ISS Expedition 16 Crew, NASA
Explanation: Looking out a window of the International Space Station brings breathtaking views. Visible vistas include a vast and colorful Earth, a deep dark sky, and an occasional spaceship sent to visit the station. Visible early last month was a Soyuz TMA-12 spacecraft carrying not only supplies but also three newcomers. The three new astronauts were Expedition 17 commander Sergei Volkov, flight engineer Oleg Kononenko, and spaceflight participant So-yeon Yi. Yi returned to Earth a few days later, while Volkov and Konenenko are scheduled to return in a few months. The docking module pictured above involved the Pirs Docking Compartment. The Expedition 17 crew, including NASA flight engineer Gregory Chamitoff, will carry out repairs on the ISS, explore new methods of living in space, and conduct research in space including the effects of space radiation on vitamin molecules.
Tomorrow's picture: sideways
Astronomy Picture of the Day
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2008 May 20
The Perseus Cluster of Galaxies
Credit & Copyright: Jean-Charles Cuillandre (CFHT) & Giovanni Anselmi (Coelum Astronomia), Hawaiian Starlight
Explanation: Here is one of the largest objects that anyone will ever see on the sky. Each of these fuzzy blobs is a galaxy, together making up the Perseus Cluster, one of the closest clusters of galaxies. The cluster is seen through a foreground of faint stars in our own Milky Way Galaxy. Near the cluster center, roughly 250 million light-years away, is the cluster's dominant galaxy NGC 1275, seen above as the large galaxy on the image left. A prodigious source of x-rays and radio emission, NGC 1275 accretes matter as gas and galaxies fall into it. The Perseus Cluster of Galaxies is part of the Pisces-Perseus supercluster spanning over 15 degrees and containing over 1,000 galaxies. At the distance of NGC 1275, this view covers about 7.5 million light-years.
Tomorrow's picture: dangerous planet
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2008 May 20
The Perseus Cluster of Galaxies
Credit & Copyright: Jean-Charles Cuillandre (CFHT) & Giovanni Anselmi (Coelum Astronomia), Hawaiian Starlight
Explanation: Here is one of the largest objects that anyone will ever see on the sky. Each of these fuzzy blobs is a galaxy, together making up the Perseus Cluster, one of the closest clusters of galaxies. The cluster is seen through a foreground of faint stars in our own Milky Way Galaxy. Near the cluster center, roughly 250 million light-years away, is the cluster's dominant galaxy NGC 1275, seen above as the large galaxy on the image left. A prodigious source of x-rays and radio emission, NGC 1275 accretes matter as gas and galaxies fall into it. The Perseus Cluster of Galaxies is part of the Pisces-Perseus supercluster spanning over 15 degrees and containing over 1,000 galaxies. At the distance of NGC 1275, this view covers about 7.5 million light-years.
Tomorrow's picture: dangerous planet
Here is another nice photo i got on the main page of NASA this morning.
i love the pictures amazing!
It would be hard to belive that we are alone in that mass of galaxies.Like 1,000x1,000x who knows how many possible planets?
^yah I would really like to see someone from the other planets from the other galaxies.. if only I could be alive in the next hundred years haha..
I think they already have been visiting here.. gov't is just hiding it
I think they already have been visiting here.. gov't is just hiding it
A great buy of the year is the C/D`s on When we Left Earth special thats being aired this month History Ch,or Discovery ch? Get a set great stuff. Now back to topic sorry had to tell the tell ITs great NASA history
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