Mars Orbiter Returns First Images
The Mars Reconnaissance Orbiter on Friday returned the first test images from its super high-resolution cameras, the most powerful photographic equipment to be trained on the Red Planet in NASA's search for water and life.
The black-and-white photos, taken by three cameras, show deep channels and layered surface debris around the planet's midsection, features that probably were formed by water, said Alfred McEwen, a mission scientist and University of Arizona professor of planetary science.
The images were taken from an altitude of 1,547 miles above the surface, about three times higher than the orbiter will be when it formally begins its science mission in November.
The spacecraft, which reached orbit on March 10, is to map about 1 percent of the Martian surface for future landings by robotic probes and human astronauts.
The resolution of the test images is comparable to those captured by the less powerful cameras of three other orbiters circling Mars, but the tests show that cameras survived the seven-month space trip that began in August.
NASA scientists will use the images to calibrate the cameras, and will later combine the images to create broader view and to add color. They are available for viewing at www.jpl.nasa.gov.
Over the next seven months, the orbiter will "aerobrake," dipping into Mars' atmosphere and gradually changing its elliptical orbit into a near-circle about 185 miles above the planet's surface. In the lower orbit, scientists will be able to distinguish surface objects as small as 3 feet (1 meter) wide, McEwen said.
The Mars Reconnaissance Orbiter has a suite of onboard instruments to map the planet's subsurface minerals, monitor its atmosphere and look for evidence of subsurface ice or water.
"At this point we have an idea that water is probably abundant on Mars in the form of ice," McEwen said. "It's not a matter of finding water on Mars but learning its importance in climate change ... and clearly it has been important to shaping the landscape."
The orbiter's first mission is to find landing sites for the Phoenix Mars Lander, set to arrive on Mars in May 2008 to dig for subsurface water ice, and for the 2009 arrival of the Mars Science Laboratory, a larger version of the twin robotic geologists Spirit and Opportunity, which have been traversing the planet's surface since 2004.
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美國宇航局的火星偵察軌道器3月24日首次傳回了火星表面照片。利用這顆探測衛(wèi)星上的超高分辨率照相機，美國宇航局將在火星上尋找水和生命的蹤跡，并為未來登陸行動挑選著陸點。
據(jù)路透社3月24報道，參與此項任務(wù)的亞利桑那大學行星學教授艾爾佛雷德·麥克尤恩說，這批黑白照片是由火星偵察軌道器（MRO）上的3臺照相機拍攝的，照片顯示，火星中部地區(qū)分布有深溝和層狀表面的巖屑，這些地貌有可能是水的運動造成的。
MRO在3月10日進入火星軌道。這批照片是在距離火星表面1547英里（約2490公里）高處拍攝的。美國宇航局的科學家們將利用這次拍攝的照片對MRO上的照相機進行校正。MRO上的設(shè)備是目前4個火星探測衛(wèi)星中最先進的，它發(fā)回的數(shù)據(jù)量將超過其余3個所發(fā)回數(shù)據(jù)量的總和。
在以后的7個月內(nèi)，MRO將緩慢沉入火星大氣層，并漸漸由橢圓形軌道過渡到距火星表面約185英里（300公里）的近圓軌道。11月正式開始工作后， MRO與火星間的距離將只有現(xiàn)在距離火星高度的四分之一。麥克尤恩說，在這個較低的軌道上，科學家們甚至能夠看清火星表面上3英尺（1米）寬的物體。 MRO上攜帶的儀器還能夠勘測地下礦藏，觀察大氣活動以及尋找地表下固態(tài)水的蹤跡。
“目前我們認為，火星上可能有大量以冰的形式存在的水”，麥克尤恩說，“但找到水并不是目的，問題是要搞清水在火星氣候演變過程中的重要意義?！?BR> MRO的第一個任務(wù)將是為鳳凰號火星登陸車和火星科學實驗室尋找合適的降落點。前者將于2008年抵達火星，搜集地下固態(tài)水，后者則是勇氣號和機遇號火星車的增強版，計劃于2009年抵達。
The Mars Reconnaissance Orbiter on Friday returned the first test images from its super high-resolution cameras, the most powerful photographic equipment to be trained on the Red Planet in NASA's search for water and life.
The black-and-white photos, taken by three cameras, show deep channels and layered surface debris around the planet's midsection, features that probably were formed by water, said Alfred McEwen, a mission scientist and University of Arizona professor of planetary science.
The images were taken from an altitude of 1,547 miles above the surface, about three times higher than the orbiter will be when it formally begins its science mission in November.
The spacecraft, which reached orbit on March 10, is to map about 1 percent of the Martian surface for future landings by robotic probes and human astronauts.
The resolution of the test images is comparable to those captured by the less powerful cameras of three other orbiters circling Mars, but the tests show that cameras survived the seven-month space trip that began in August.
NASA scientists will use the images to calibrate the cameras, and will later combine the images to create broader view and to add color. They are available for viewing at www.jpl.nasa.gov.
Over the next seven months, the orbiter will "aerobrake," dipping into Mars' atmosphere and gradually changing its elliptical orbit into a near-circle about 185 miles above the planet's surface. In the lower orbit, scientists will be able to distinguish surface objects as small as 3 feet (1 meter) wide, McEwen said.
The Mars Reconnaissance Orbiter has a suite of onboard instruments to map the planet's subsurface minerals, monitor its atmosphere and look for evidence of subsurface ice or water.
"At this point we have an idea that water is probably abundant on Mars in the form of ice," McEwen said. "It's not a matter of finding water on Mars but learning its importance in climate change ... and clearly it has been important to shaping the landscape."
The orbiter's first mission is to find landing sites for the Phoenix Mars Lander, set to arrive on Mars in May 2008 to dig for subsurface water ice, and for the 2009 arrival of the Mars Science Laboratory, a larger version of the twin robotic geologists Spirit and Opportunity, which have been traversing the planet's surface since 2004.
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美國宇航局的火星偵察軌道器3月24日首次傳回了火星表面照片。利用這顆探測衛(wèi)星上的超高分辨率照相機，美國宇航局將在火星上尋找水和生命的蹤跡，并為未來登陸行動挑選著陸點。
據(jù)路透社3月24報道，參與此項任務(wù)的亞利桑那大學行星學教授艾爾佛雷德·麥克尤恩說，這批黑白照片是由火星偵察軌道器（MRO）上的3臺照相機拍攝的，照片顯示，火星中部地區(qū)分布有深溝和層狀表面的巖屑，這些地貌有可能是水的運動造成的。
MRO在3月10日進入火星軌道。這批照片是在距離火星表面1547英里（約2490公里）高處拍攝的。美國宇航局的科學家們將利用這次拍攝的照片對MRO上的照相機進行校正。MRO上的設(shè)備是目前4個火星探測衛(wèi)星中最先進的，它發(fā)回的數(shù)據(jù)量將超過其余3個所發(fā)回數(shù)據(jù)量的總和。
在以后的7個月內(nèi)，MRO將緩慢沉入火星大氣層，并漸漸由橢圓形軌道過渡到距火星表面約185英里（300公里）的近圓軌道。11月正式開始工作后， MRO與火星間的距離將只有現(xiàn)在距離火星高度的四分之一。麥克尤恩說，在這個較低的軌道上，科學家們甚至能夠看清火星表面上3英尺（1米）寬的物體。 MRO上攜帶的儀器還能夠勘測地下礦藏，觀察大氣活動以及尋找地表下固態(tài)水的蹤跡。
“目前我們認為，火星上可能有大量以冰的形式存在的水”，麥克尤恩說，“但找到水并不是目的，問題是要搞清水在火星氣候演變過程中的重要意義?！?BR> MRO的第一個任務(wù)將是為鳳凰號火星登陸車和火星科學實驗室尋找合適的降落點。前者將于2008年抵達火星，搜集地下固態(tài)水，后者則是勇氣號和機遇號火星車的增強版，計劃于2009年抵達。