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A Mystery In Gamma Rays
| Title |
A Mystery In Gamma Rays |
| Explanation |
Gamma rays [ http://cossc.gsfc.nasa.gov/epo/vu/ ] are the most energetic form of light, packing a million or more times the energy of visible light photons. If you could see gamma rays, the familiar skyscape [ http://antwrp.gsfc.nasa.gov/apod/ap040304.html ] of steady stars would be replaced [ http://antwrp.gsfc.nasa.gov/apod/ap980321.html ] by some of the most bizarre objects known [ http://skyandtelescope.com/howto/basics/ article_240_1.asp ] to modern astrophysics [ http://ads.harvard.edu/ ] -- and some which are "unknown". When the EGRET [ http://lheawww.gsfc.nasa.gov/docs/gamcosray/EGRET/ instrument_description.html ] instrument on the orbiting Compton Gamma-ray Observatory [ http://antwrp.gsfc.nasa.gov/apod/ap000408.html ] surveyed the sky in the 1990s, it cataloged 271 celestial sources [ http://cossc.gsfc.nasa.gov/gamcat/catform.html ] of high-energy gamma-rays. Researchers identified some with exotic black holes [ http://antwrp.gsfc.nasa.gov/apod/ap980729.html ], neutron stars [ http://antwrp.gsfc.nasa.gov/apod/ap010719.html ], and distant flaring galaxies [ http://antwrp.gsfc.nasa.gov/apod/ap981226.html ]. But 170 of the cataloged sources, shown in the above all-sky map, remain unidentified. Many sources [ http://pao.gsfc.nasa.gov/gsfc/spacesci/structure/cgro.htm ] in this gamma-ray mystery map likely belong to already known classes of gamma-ray emitters and are simply obscured or too faint to be otherwise positively identified. However, astronomers have called attention [ http://pao.gsfc.nasa.gov/gsfc/spacesci/structure/cgro.htm#press ] to the ribbon of sources winding through the plane of the galaxy, projected here along the middle of the map, which may represent a large unknown class [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query? bibcode=2000HEAD...32.4007G&db_key=AST&high=3af6c03e8125794 ] of galactic gamma-ray emitters. In any event, the unidentified sources could remain a mystery until the planned launch of the more sensitive Gamma-ray Large Area Space Telescope [ http://www-glast.sonoma.edu/ ] in 2007. |
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KENNEDY SPACE CENTER, FLA. -
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| Description |
KENNEDY SPACE CENTER, FLA. -- A snowy egret is spotted in the midst of reeds near a pond on NASA's Kennedy Space Center. A type of heron, the snowy egret inhabits salt marshes, ponds, rice fields and shallow coastal bays ranging from Maine to southern South America on the east coast. It can also be found in California and Oklahoma to the Gulf of Mexico. KSC shares a boundary with the Merritt Island Wildlife Nature Refuge. The refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. In addition, the Refuge supports 19 endangered or threatened wildlife species on Federal or State lists, more than any other single refuge in the U.S. Photo credit: NASA/Ken Thornsley |
| Release Date |
01/19/2007 |
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KENNEDY SPACE CENTER, FLA. -
…
| Description |
KENNEDY SPACE CENTER, FLA. -- A snowy egret is on the lookout for food in a pond on NASA's Kennedy Space Center. A type of heron, the snowy egret inhabits salt marshes, ponds, rice fields and shallow coastal bays ranging from Maine to southern South America on the east coast. It can also be found in California and Oklahoma to the Gulf of Mexico. KSC shares a boundary with the Merritt Island Wildlife Nature Refuge. The refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. In addition, the Refuge supports 19 endangered or threatened wildlife species on Federal or State lists, more than any other single refuge in the U.S. Photo credit: NASA/Ken Thornsley |
| Release Date |
01/19/2007 |
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KENNEDY SPACE CENTER, FLA. -
…
| Description |
KENNEDY SPACE CENTER, FLA. -- A snowy egret marches through a pond near Kennedy Space Center, looking for food. The snowy egret can be identified by its slender black bill, black legs and yellow feet. This species inhabits salt marshes, ponds, rice field and shallow coastal bays along the coast from Maine to southern South America. They are also found in northern California, Texas and Oklahoma. KSC shares a boundary with the Merritt Island National Wildlife Refuge, which surrounds it. The refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. In addition, the refuge supports 19 endangered or threatened wildlife species on Federal or State lists, more than any other single refuge in the U.S. Photo credit: NASA/Ken Thornsley |
| Release Date |
03/29/2007 |
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KENNEDY SPACE CENTER, FLA. -
…
| Description |
KENNEDY SPACE CENTER, FLA. -- A snowy egret perches on dead limbs in the Indian River near Kennedy Space Center. A type of heron, the snowy egret inhabits salt marshes, ponds, rice fields and shallow coastal bays ranging from Maine to southern South America on the east coast. It can also be found in California and Oklahoma to the Gulf of Mexico. KSC shares a boundary with the Merritt Island Wildlife Nature Refuge. The refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. In addition, the Refuge supports 19 endangered or threatened wildlife species on Federal or State lists, more than any other single refuge in the U.S. Photo credit: NASA/Dimitri Gerondidakis |
| Release Date |
04/11/2007 |
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KENNEDY SPACE CENTER, FLA. -
…
| Description |
KENNEDY SPACE CENTER, FLA. -- A snowy egret prepares for flight from its perch in the Indian River near Kennedy Space Center. A type of heron, the snowy egret inhabits salt marshes, ponds, rice fields and shallow coastal bays ranging from Maine to southern South America on the east coast. It can also be found in California and Oklahoma to the Gulf of Mexico. KSC shares a boundary with the Merritt Island Wildlife Nature Refuge. The refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. In addition, the Refuge supports 19 endangered or threatened wildlife species on Federal or State lists, more than any other single refuge in the U.S. Photo credit: NASA/Dimitri Gerondidakis |
| Release Date |
04/11/2007 |
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KENNEDY SPACE CENTER, FLA. -
…
| Description |
KENNEDY SPACE CENTER, FLA. -- A snowy egret perches on dead limbs in the Indian River near Kennedy Space Center. A type of heron, the snowy egret inhabits salt marshes, ponds, rice fields and shallow coastal bays ranging from Maine to southern South America on the east coast. It can also be found in California and Oklahoma to the Gulf of Mexico. KSC shares a boundary with the Merritt Island Wildlife Nature Refuge. The refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. In addition, the Refuge supports 19 endangered or threatened wildlife species on Federal or State lists, more than any other single refuge in the U.S. Photo credit: NASA/Dimitri Gerondidakis |
| Release Date |
04/11/2007 |
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