WASHINGTON - The existence of ice on Mars was confirmed Friday by NASA scientists, the first time frozen water has been sampled on another planet. Water in liquid form is an essential ingredient for life.
Whitish, dice-sized chunks, dug from the rocky red soil and warmed in the sun, vanished four days after the National Aeronautics and Space Administration's Phoenix probe dug them up June 15.
They confirm what NASA satellites have suggested for years: Frozen water exists several centimeters beneath Mars' surface.Now, scientists can tackle the key question they hope to answer: Did the ice ever melt and turn Mars into a habitable place?Scientists believe ice exists on planets including Pluto, though Phoenix is the first probe to confirm it on the ground.
The survey is part of NASA's theme in Mars exploration: follow the water. "We've hit what we're looking for," said Mark Lemmon, an atmospheric scientist at Texas A&M University in College Station and co-investigator on the NASA project.
"The job now is to find out what's mixed in with the ice."
The Phoenix's robotic arm also hit a hard surface Thursday while digging in a different spot, raising scientists' hopes they might uncover a larger ice layer to sample, NASA said.NASA satellites suggest about a quarter of Mars has ice beneath the surface, primarily at the polar regions.
The agency's plan is to gather up ice and dirt, then deliver it to the Phoenix's ovens.
The matchbox-size ovens will then bake the sample.On Mars, the boiling point of water is just 4 degrees Celsius.
Under the planet's faint atmosphere, the water will quickly vaporize, principal investigator Peter Smith of the University of Arizona in Tucson said.
Before it does, the probe will analyze the samples for any long-chain carbon molecules such as amino acids, the building blocks of life.
The University of Arizona team ruled out the possibility the material might be dry ice or salt.
Salt wouldn't vaporize, and dry ice exists at much cooler temperatures than found at the Phoenix landing site.
Source
机械臂刨开火星地表触及冰层，简易的农学小发明可测土壤湿度
美国“凤凰”号火星探测项目研究人员19日说，“凤凰”号火星着陆探测器在火星北极地表挖掘时发现的白色物质就是冰。此外，为探测火星土壤的含水量，“凤凰”号上有一个简易装置。有趣的是，这项发明源自一项农学研究，最初用作检测花生荚周围土壤湿度。
太阳辐射导致冰蒸发
美国航空航天局说，“凤凰”号19日检测15日挖掘的沟槽时，发现沟槽中的一些白色物质碎块已完全消失。
亚利桑那大学“凤凰”号火星探测项目研究人员彼得·史密斯说，这一现象说明，白色物质是冰，太阳辐射导致冰蒸发，“盐不可能发生这种变化”。
国航空航天局说，“凤凰”号机械臂19日挖掘新沟槽时，再次触及坚硬物质。根据过去几天的发现，“凤凰”号可能找到了火星地表下的冰层。
“凤凰”号5月25日在火星北极附近区域着陆，它将在为期3个月的探测任务中探寻可能存在的火星地下冰层。 巧用农学小发明
另据美联社18日报道，农学家蒂姆·威廉姆斯1987年与华盛顿州立大学的土壤学家盖隆·坎贝尔及其团队合作时，开始设计一个可以检测花生荚周围土壤湿度的装置。
这个装置包含两根彼此平行的针，一根由定量能量予以加热，另一根则在两根针双双插入土壤后检测被加热的针的冷却情况，以此测定土壤湿度。
去年，有关部门告诉威廉姆斯，这个小玩意将被装在“凤凰”号机械臂上。坎贝尔所在的德卡贡公司对它加以改造，除了增强耐用性，还增加了测量热量、电属性、气体温度、风速和水蒸气等功能。
38年来，威廉姆斯致力于研究花生。他发明了不少简易装置，包括检测农作物辐射量的装置和测试植株叶片对地表覆盖程度的装置。前者有助于研究人员更好地掌握农作物产量，后者用于估算从叶片间隙到达地表的光照量。
Source
Whitish, dice-sized chunks, dug from the rocky red soil and warmed in the sun, vanished four days after the National Aeronautics and Space Administration's Phoenix probe dug them up June 15.
They confirm what NASA satellites have suggested for years: Frozen water exists several centimeters beneath Mars' surface.Now, scientists can tackle the key question they hope to answer: Did the ice ever melt and turn Mars into a habitable place?Scientists believe ice exists on planets including Pluto, though Phoenix is the first probe to confirm it on the ground.
The survey is part of NASA's theme in Mars exploration: follow the water. "We've hit what we're looking for," said Mark Lemmon, an atmospheric scientist at Texas A&M University in College Station and co-investigator on the NASA project.
"The job now is to find out what's mixed in with the ice."
The Phoenix's robotic arm also hit a hard surface Thursday while digging in a different spot, raising scientists' hopes they might uncover a larger ice layer to sample, NASA said.NASA satellites suggest about a quarter of Mars has ice beneath the surface, primarily at the polar regions.
The agency's plan is to gather up ice and dirt, then deliver it to the Phoenix's ovens.
The matchbox-size ovens will then bake the sample.On Mars, the boiling point of water is just 4 degrees Celsius.
Under the planet's faint atmosphere, the water will quickly vaporize, principal investigator Peter Smith of the University of Arizona in Tucson said.
Before it does, the probe will analyze the samples for any long-chain carbon molecules such as amino acids, the building blocks of life.
The University of Arizona team ruled out the possibility the material might be dry ice or salt.
Salt wouldn't vaporize, and dry ice exists at much cooler temperatures than found at the Phoenix landing site.
Source
机械臂刨开火星地表触及冰层，简易的农学小发明可测土壤湿度
美国“凤凰”号火星探测项目研究人员19日说，“凤凰”号火星着陆探测器在火星北极地表挖掘时发现的白色物质就是冰。此外，为探测火星土壤的含水量，“凤凰”号上有一个简易装置。有趣的是，这项发明源自一项农学研究，最初用作检测花生荚周围土壤湿度。
太阳辐射导致冰蒸发
美国航空航天局说，“凤凰”号19日检测15日挖掘的沟槽时，发现沟槽中的一些白色物质碎块已完全消失。
亚利桑那大学“凤凰”号火星探测项目研究人员彼得·史密斯说，这一现象说明，白色物质是冰，太阳辐射导致冰蒸发，“盐不可能发生这种变化”。
国航空航天局说，“凤凰”号机械臂19日挖掘新沟槽时，再次触及坚硬物质。根据过去几天的发现，“凤凰”号可能找到了火星地表下的冰层。
“凤凰”号5月25日在火星北极附近区域着陆，它将在为期3个月的探测任务中探寻可能存在的火星地下冰层。 巧用农学小发明
另据美联社18日报道，农学家蒂姆·威廉姆斯1987年与华盛顿州立大学的土壤学家盖隆·坎贝尔及其团队合作时，开始设计一个可以检测花生荚周围土壤湿度的装置。
这个装置包含两根彼此平行的针，一根由定量能量予以加热，另一根则在两根针双双插入土壤后检测被加热的针的冷却情况，以此测定土壤湿度。
去年，有关部门告诉威廉姆斯，这个小玩意将被装在“凤凰”号机械臂上。坎贝尔所在的德卡贡公司对它加以改造，除了增强耐用性，还增加了测量热量、电属性、气体温度、风速和水蒸气等功能。
38年来，威廉姆斯致力于研究花生。他发明了不少简易装置，包括检测农作物辐射量的装置和测试植株叶片对地表覆盖程度的装置。前者有助于研究人员更好地掌握农作物产量，后者用于估算从叶片间隙到达地表的光照量。
Source
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