论文标题
彗星糖醛作为前RNA分子的来源
Cometary glycolaldehyde as a source of pre-RNA molecules
论文作者
论文摘要
在多个外星环境中检测到了超过200个分子，包括糖醛（C2（H2O）2，GLA），这是一种在星际培养基区域中检测到的两碳糖前体。它最近对彗星67p/churyumov-gerasimenko核的原位检测以及通过其他人的远程观察结果提供了诱人的证据，表明大多数（如果不是全部）彗星在大多数（如果不是全部）彗星上都是常见的。在NASA的约翰逊航天中心的实验冲击实验室进行的影响实验表明，与蒙莫利隆岩粘土混合的GLA和GLA样品可以在4.5 GPA至25 GPA的压力范围内生存。这些实验结果表明，在单个彗星上观察到的GLA量，并假设有单调的影响率，这些实验结果表明，高达10^23 kg的彗星GLA可以生存在撞击递送中，并具有大量的三分，递三糖，脱发，乙酸，乙醇酸，乙烯乙烯和乙烯乙二醇或交付。重要的是，与早期太阳系中冲击通量的轮廓无关，GLA的彗星输送将提供（并可能继续提供）folose反应（形成核糖）和Strecker反应（形成氨基酸）的起始材料的储层。因此，彗星可能是我们所知道的生命所需的起始分子的重要递送工具。
Over 200 molecules have been detected in multiple extraterrestrial environments, including glycolaldehyde (C2(H2O)2, GLA), a two-carbon sugar precursor that has been detected in regions of the interstellar medium. Its recent in situ detection on the nucleus of comet 67P/Churyumov-Gerasimenko and via remote observations in the comae of others, provides tantalizing evidence that it is common on most (if not all) comets. Impact experiments conducted at the Experimental Impact Laboratory at NASA's Johnson Space Center have shown that samples of GLA and GLA mixed with montmorillonite clays can survive impact delivery in the pressure range of 4.5 GPa to 25 GPa. Extrapolated to amounts of GLA observed on individual comets and assuming a monotonic impact rate in the first billion years of solar system history, these experimental results show that up to 10^23 kg of cometary GLA could have survived impact delivery, with substantial amounts of threose, erythrose, glycolic acid, and ethylene glycol also produced or delivered. Importantly, independent of the profile of the impact flux in the early solar system, comet delivery of GLA would have provided (and may continue to provide) a reservoir of starting material for the formose reaction (to form ribose) and the Strecker reaction (to form amino acids). Thus, comets may have been important delivery vehicles for starting molecules necessary for life as we know it.
