标题： 彗星67P尘埃彗发中的含氧有机分子：异环化合物丰富的首个证据 显示英文标题

标题： Oxygen-bearing organic molecules in comet 67P's dusty coma: first evidence for abundant heterocycles

摘要： 地球生物分子的复杂性令人困惑，这推动了对星际介质（ISM）中复杂有机分子的搜寻，并激励了许多关于来自陨石和行星际尘埃颗粒（IDPs）到彗星和小行星的非地球有机物储库的原位研究。 67P/楚留莫夫-格拉希门克彗星（67P）——迄今为止研究最充分的彗星——已被欧洲航天局的罗塞塔航天器访问并伴随了两年。 在67P近日点附近和多尘条件下，机载高分辨率质谱仪提供了对该彗星化学复杂性的惊人一瞥。 在这项工作中，我们前所未有地详细分析了含氧有机挥发物。 通过比较67P的物质清单与在ISM中检测到的分子、其他彗星中的分子以及从默奇森陨石中提取的可溶性有机物（SOM）中的分子，我们还强调了不同物种化学基团的（前）生物相关性。 我们报告了大量存在丰富的非地球含氧杂环化合物（其相对于甲醇的丰度通常约为10%，相对误差范围为30-50%）以及其他分子类别的各种代表，如羧酸和酯、醛、酮和醇。 与纯碳氢化合物类似，某些氢化形式似乎比其去氢化对应物更占主导地位。 一个有趣的例子是四氢呋喃（THF），因为它可能是ISM中寻找的一种更有希望的候选物，而不是长期以来寻找的呋喃本身。 我们的发现不仅支持并指导未来努力调查空间中化学复杂性的起源，而且强烈鼓励对实验室中天体物理冰模拟物以及建模中的未分支与分支以及氢化与去氢化物种的比例进行研究。 显示英文摘要

摘要： The puzzling complexity of terrestrial biomolecules is driving the search for complex organic molecules in the Interstellar Medium (ISM) and serves as a motivation for many in situ studies of reservoirs of extraterrestrial organics from meteorites and interplanetary dust particles (IDPs) to comets and asteroids. Comet 67P/Churyumov-Gerasimenko (67P) -- the best-studied comet to date -- has been visited and accompanied for two years by the European Space Agency's Rosetta spacecraft. Around 67P's perihelion and under dusty conditions, the high-resolution mass spectrometer on board provided a spectacular glimpse into this comet's chemical complexity. For this work, we analyzed in unprecedented detail the O-bearing organic volatiles. In a comparison of 67P's inventory to molecules detected in the ISM, in other comets, and in Soluble Organic Matter (SOM) extracted from the Murchison meteorite, we also highlight the (pre)biotic relevance of different chemical groups of species. We report first evidence for abundant extraterrestrial O-bearing heterocycles (with abundances relative to methanol often on the order of 10% with a relative error margin of 30-50%) and various representatives of other molecule classes such as carboxylic acids and esters, aldehydes, ketones, and alcohols. Like with the pure hydrocarbons, some hydrogenated forms seem to be dominant over their dehydrogenated counterparts. An interesting example is tetrahydrofuran (THF) as it might be a more promising candidate for searches in the ISM than the long-sought furan itself. Our findings not only support and guide future efforts to investigate the origins of chemical complexity in space, but also they strongly encourage studies of, e.g., the ratios of unbranched vs. branched and hydrogenated vs. dehydrogenated species in astrophysical ice analogs in the laboratory as well as by modeling.