Organic ablation products of extraterrestrial objects

当物体从太空坠落到地球上时，我们的注意力集中在这些燃烧事件的岩石残骸上是可以理解的，我们可以收集和研究这些残骸。然而，大量的外星物质从未到达地球表面，而是以气体的形式蒸馏出来。这些贡献改变了我们的大气，增加了影响气候的有机气体，破坏了阻隔太阳有害辐射的臭氧层。在火星等其他星球上，它们可能会模仿生物的气体产物，而正是这些产物激发了科学家们在太阳系其他地方寻找生命。有趣的是，这些气体的增加使早期的火星保持温暖和潮湿，所以生命可以在地球以外的地方开始。为了弄清这些可能性，我们的研究将使用收集到的地外物质在实验室里重现气体产生的过程。结果将被输入计算机模拟，以提供地球和火星在其历史上以这种方式产生的气体量。我们将为甲烷等气体设定一个下限，因为甲烷可能被误认为火星上存在生命的证据。该项目还将帮助我们了解40亿年前太空尘埃是如何使地球和火星变得温暖潮湿的，以及它是如何使今天的地球变得更加敌对的。

When object fall to the Earth from space it is understandable that our focus is on the rocky remains of these fiery events that we can collect and study. Yet large amounts of extraterrestrial material never make it to the surface but are distilled off as gas. These contributions change our atmosphere, adding organic gases that affect our climate and destroy the protective ozone shield that cuts out damaging radiation from the Sun. On other worlds, such as Mars, they may mimic the gaseous products of biology that excite scientists looking for life elsewhere in the Solar System. Interestingly, these gas additions my have kept early Mars warm and wet so that life could have kick-started in places other than on Earth. To get to the bottom of these possibilities our research will use collected extraterrestrial material to reproduce the gas generation events in the laboratory. Results will be fed into computer simulations to provide the amounts of gas produced in this way for Earth and Mars through their history. We will produce a lower limit for gases such as methane that may be mistaken for evidence of life on Mars. The project will also help us understand how space dust made Earth and Mars warm and wet four billion years ago and how it may be making the Earth more hostile today.