"勇气"号意外发现力证 火星上可能有水有原始生命

经过多个探测器的努力，科学家已经不止一次在火星上发现了有水的证据。但是，美国航空航天局“勇气”号火星探测器的最新发现还是让科学家们高度兴奋，因为“勇气”号在轮子受损的情况下，不经意间找到了迄今有关火星有水的最强有力证据！这意味着火星上可能曾经有过生命。　　
    意外蹭出特殊火星土
　
　综合英国《每日电讯报》等媒体报道，当地时间5月21日，美国航空航天局公布了 “勇气”号发回的最新照片，这些照片以非常不同寻常的证据表明，火星上曾经有水。
　
　不过，这一发现其实很意外，说起来还得益于“勇气”号一个出问题的轮子。早在2004年4月，火星孪生探测器“勇气”号和“机遇”号就已完成最初设定的探测任务。此后，尽管显示出逐渐老化的迹象，但这两个探测器一直坚持“奋战”在火星上。
　
　最近，“勇气”号六个轮子中的一个已经不能旋转，因此，它经过的火星表面都会形成一道道深深的“沟壑”。
　
　有意思的是，正是这些不经意的动作带来了火星探测史上最重要的发现！因为“沟壑”中被“刮蹭”过的火星土显现出明亮的颜色，而“勇气”号对这些特殊的火星土进行化学分析后发现，其中硅石的含量竟然高达90％。
　
　美国航空航天局的科学家说：“我们观测了很多被‘刮蹭’的火星土，这是我们第一次发现硅石。”
　
　火星或有原始生命
　
　这一重大发现给科学家们带来了莫大的兴奋。负责“勇气”号探测工作的科学家史蒂夫说，在航空航天局发布照片现场，可以听到人们的惊叹声。
　
　科学家们介绍说，“勇气”号发现火星土里富含硅石，而硅石的沉积是需要大量的水作为条件的。因此，火星过去可能比现在更湿润，这同时为“火星生命说”添加了新的重要证据。科学家们开始猜测，火星这样的条件和环境很可能适合生命的生存。

　　目前，还不清楚这些硅石沉积物究竟是如何形成的，但美国航空航天局的科学家说，有一种可能是火山活动产生的酸水蒸气和土壤的混合导致了硅石的沉积，还有另一种可能则是温泉环境作用的结果。
　
　史蒂夫激动地表示：“这让人们不禁会猜想，火星上是否有生命存在？最新的发现为过去提出的火星适合生命存在的说法添加了新证据。”
　
　迄今为止，美国航空航天局“勇气”号和“机遇”号火星探测器、“火星侦察卫星”探测器等都已经发现了不少火星上可能曾经有水的证据，如曾被水浸泡并富含硫磺的土壤、变形的矿物等等。
　
　此外，今年3月，欧洲航天局的“火星快车”号探测器发回的数据显示，在火星南极存在一大片广袤的冰盖，如果融化，整个火星表面将被11米深的水层所覆盖。
　　
原始图片：PIA09403: Silica-Rich Soil in Gusev Crater

Original Caption Released with Image: NASA's Mars Exploration Rover Spirit has found a patch of bright-toned soil so rich in silica that scientists propose water must have been involved in concentrating it.

The silica-rich patch, informally named "Gertrude Weise" after a player in the All-American Girls Professional Baseball League, was exposed when Spirit drove over it during the 1,150th Martian day, or sol, of Spirit's Mars surface mission (March 29, 2007). One of Spirit's six wheels no longer rotates, so it leaves a deep track as it drags through soil. Most patches of disturbed, bright soil that Spirit had investigated previously are rich in sulfur, but this one has very little sulfur and is about 90 percent silica.

Spirit's panoramic camera imaged the bright patch through various filters on Sol 1,158 (April 6). This approximately true-color image combines images taken through three different filters. The track of disturbed soil is roughly 20 centimeters (8 inches) wide.
Spirit's miniature thermal emission spectrometer, which can assess a target's mineral composition from a distance, examined the Gertrude Weise patch on Sol 1,172 (April 20). The indications it found for silica in the overturned soil prompted a decision to drive Spirit close enough to touch the soil with the alpha particle X-ray spectrometer, a chemical analyzer at the end of Spirit's robotic arm. The alpha particle X-ray spectrometer collected data about this target on sols 1,189 and 1,190 (May 8 and May 9) and produced the finding of approximately 90 percent silica.

Silica is silicon dioxide. On Earth, it commonly occurs as the crystalline mineral quartz and is the main ingredient in window glass. The Martian silica at Gertrude Weise is non-crystalline, with no detectable quartz.
In most cases, water is required to produce such a concentrated deposit of silica, according to members of the rover science team. One possible origin for the silica could have been interaction of soil with acidic steam produced by volcanic activity. Another could have been from water in a hot spring environment.

PIA09491: Silica-Rich Soil Found by Spirit

NASA's Mars Exploration Rover Spirit has found a patch of bright-toned soil so rich in silica that scientists propose water must have been involved in concentrating it.

The silica-rich patch, informally named "Gertrude Weise" after a player in the All-American Girls Professional Baseball League, was exposed when Spirit drove over it during the 1,150th Martian day, or sol, of Spirit's Mars surface mission (March 29, 2007). One of Spirit's six wheels no longer rotates, so it leaves a deep track as it drags through soil. Most patches of disturbed, bright soil that Spirit had investigated previously are rich in sulfur, but this one has very little sulfur and is about 90 percent silica.

  This image is a approximately true-color composite of three images taken through different filters by Spirit's panoramic camera on Sol 1,187 (May 6). The track of disturbed soil is roughly 20 centimeters (8 inches) wide.
Spirit's miniature thermal emission spectrometer, which can assess a target's mineral composition from a distance, examined the Gertrude Weise patch on Sol 1,172 (April 20). The indications it found for silica in the overturned soil prompted a decision to drive Spirit close enough to touch the soil with the alpha particle X-ray spectrometer, a chemical analyzer at the end of Spirit's robotic arm. The alpha particle X-ray spectrometer collected data about this target on sols 1,189 and 1,190 (May 8 and May 9) and produced the finding of approximately 90 percent silica.

Silica is silicon dioxide. On Earth, it commonly occurs as the crystalline mineral quartz and is the main ingredient in window glass. The Martian silica at Gertrude Weise is non-crystalline, with no detectable quartz.
In most cases, water is required to produce such a concentrated deposit of silica, according to members of the rover science team. One possible origin for the silica could have been interaction of soil with acidic steam produced by volcanic activity. Another could have been from water in a hot spring environment.

有点意思~看来科学探索也需要运气啊

天时占尽呀     真想上去看看::0022::

请访问“MSN嫦娥奔月”中的“嘿！火星”。

火星有水是一定的，主要是量

他的文明如果比我们发展呢？