文章来源:未知 文章作者:meng 发布时间:2010-07-02 02:30 字体: [ ]  进入论坛

Up to now scientists thought that the trace amounts(微量) of carbon on the surface of the Moon came from the solar wind. Now researchers at the Carnegie Institution's Geophysical Laboratory have detected and dated Moon carbon in the form of graphite(石墨) —the sooty(乌黑的) stuff of pencil lead—which survived from the late heavy bombardment(重型轰炸机部队) era 3.8 billion years ago. The researchers found instances of graphite and a form of rolled graphite called graphite whiskers(胡须) that could only form in very high temperature reactions initiated1 by an impact. The discovery also means that the Moon potentially holds a record of the meteoritic2(陨星的) carbon input3 to the Earth-Moon system, when life was just beginning to emerge on Earth. The research is published in the July 2, 2010, issue of Science. "The Solar System was chaotic4 with countless5 colliding objects 3.8 billion years ago," explained lead author Andrew Steele. "Volatiles—compounds like water and elements like carbon were vaporized under that heat and shock. These materials were critical to the creation of life on Earth. Our team analyzed6 Moon rocks collected from the Mare7 Serenitatis impact crater8 visited by the Apollo 17 mission. In the past, researchers tried to extract the carbon from Moon material, but the only carbon definitively9 identified came from the solar wind. We used a different technique. We looked at thin rock slices and fresh surfaces using a mapping technique called confocal(共焦的) Raman imaging spectroscopy(光谱学) . This technique identifies minerals and carbon species and their spatial10 relationship(空间关系) to each other beneath the surface of a sample. We were really surprised at the discovery of graphite and graphite whiskers, we were not expecting to see anything like this."

The scientists ruled out the possibility that the graphite was a result of contamination(污染) , because graphite whiskers, in particular, form under very hot conditions, between 1830° F and 6500° F (1273-3900 Kelvin). They also ruled out that the solar wind was the source, because the particles of graphite and graphite whiskers were much larger than the carbon that is implanted by the solar wind and, while contamination occurred throughout the sample, the graphite was restricted to a discrete11(离散的,不连续的) blackened area of the sample.

"We believe that the carbon we detected either came from the object that made the impact basin, or it condensed from the carbon-rich gas that was released during impact, said coauthor Francis McCubbin. "The most exciting prospect12 from the discovery is that we now know that the Moon holds a record of that period and the materials that contributed to the rise of life on Earth."

"Furthermore, it shows that modern spatially13 resolved techniques can be used to discover further surprises in the now 40-year-old Apollo collection," remarked Mihaela Glamoclija another coauthor on the study.


1 initiated 9cd5622f36ab9090359c3cf3ca4ddda3     
n. 创始人 adj. 新加入的 vt. 开始,创始,启蒙,介绍加入
  • He has not yet been thoroughly initiated into the mysteries of computers. 他对计算机的奥秘尚未入门。
  • The artist initiated the girl into the art world in France. 这个艺术家介绍这个女孩加入巴黎艺术界。
2 meteoritic 764fbc41c009161f6b18cf20096cc96b     
  • The momentum of the particles was deduced from meteoritic velocities. 粒子的冲量可以从陨石速度推导出来。 来自互联网
3 input X6lxm     
  • I will forever be grateful for his considerable input.我将永远感激他的大量投入。
  • All this information had to be input onto the computer.所有这些信息都必须输入计算机。
4 chaotic rUTyD     
  • Things have been getting chaotic in the office recently.最近办公室的情况越来越乱了。
  • The traffic in the city was chaotic.这城市的交通糟透了。
5 countless 7vqz9L     
  • In the war countless innocent people lost their lives.在这场战争中无数无辜的人丧失了性命。
  • I've told you countless times.我已经告诉你无数遍了。
6 analyzed 483f1acae53789fbee273a644fdcda80     
v.分析( analyze的过去式和过去分词 );分解;解释;对…进行心理分析
  • The doctors analyzed the blood sample for anemia. 医生们分析了贫血的血样。 来自《简明英汉词典》
  • The young man did not analyze the process of his captivation and enrapturement, for love to him was a mystery and could not be analyzed. 这年轻人没有分析自己蛊惑著迷的过程,因为对他来说,爱是个不可分析的迷。 来自《简明英汉词典》
7 mare Y24y3     
  • The mare has just thrown a foal in the stable.那匹母马刚刚在马厩里产下了一只小马驹。
  • The mare foundered under the heavy load and collapsed in the road.那母马因负载过重而倒在路上。
8 crater WofzH     
  • With a telescope you can see the huge crater of Ve-suvius.用望远镜你能看到巨大的维苏威火山口。
  • They came to the lip of a dead crater.他们来到了一个死火山口。
9 definitively bfa3c9e3e641847693ee64d5d8ab604b     
  • None of the three super-states could be definitively conquered even by the other two in combination. 三个超级国家中的任何一国都不可能被任何两国的联盟所绝对打败。 来自英汉文学
  • Therefore, nothing can ever be definitively proved with a photograph. 因此,没有什么可以明确了一张照片。 来自互联网
10 spatial gvcww     
  • This part of brain judges the spatial relationship between objects.大脑的这部分判断物体间的空间关系。
  • They said that time is the feeling of spatial displacement.他们说时间是空间位移的感觉。
11 discrete 1Z5zn     
  • The picture consists of a lot of discrete spots of colour.这幅画由许多不相连的色点组成。
  • Most staple fibers are discrete,individual entities.大多数短纤维是不联系的单独实体。
12 prospect P01zn     
  • This state of things holds out a cheerful prospect.事态呈现出可喜的前景。
  • The prospect became more evident.前景变得更加明朗了。
13 spatially ca2278711fa6d1d851ea605dea2e8224     
  • A well-defined array of stable fringes results and the field is spatially coherent. 结果得到一组完全确定的稳定条纹,而光场是空间相干的。
  • The units are collaged together by a serial tectonic spatially and temporally. 这些构造单元是由构造原因,依一定的时空序列拼贴在一起的。
TAG标签: moon carbon graphite