A New Search for Amino Acid Precursors on Icy Solar System Objects with Improved Spectroscopic Parameters

[00:85614 . 00]已经在陨石、彗星和星际介质（ISM）中发现了氨基酸前体（AAPs）。此外，这些前体（HCN， nh3和ch3oh）在10 K水冰基质中用紫外光子照射形成甘氨酸，而没有发生任何水化学反应。西南研究所（Southwest Research Institute）的艾略特·杨（Eliot Young）博士将领导一个项目，对太阳系中的16个冰体进行调查，以寻找aap。目的是评估aap在太阳系冰体中的分布，并确定aap在什么条件下可以生存并参与生命前化学。杨预计这次望远镜调查将比以往任何一次调查都更敏感地发现aap的存在。研究小组的工作主要集中在三个方面：1。用NIRSPEC在3 - 5毫米处观测。3 - 5mm光谱范围包含了aap的基本跃迁。这些比通常观察到的泛音过渡强一个数量级。这项突破是nirspec，一个安装在夏威夷莫纳克亚山凯克望远镜上的1 - 5毫米光谱仪，它将捕捉到像冥卫一这样微弱的目标。新的光学常数：光谱数据的解释需要精确的光学常数。该团队将在各种温度下以及在水和氮基质中生成AAP冰样品。3. 更精确的光谱建模：将根据蒙特卡罗结果对当前的hake代码进行修改。这将允许更精确地拟合明亮的冰，其中散射是非各向同性的，以及虚指数接近1的情况。这项观测和分析计划有望在整个太阳系中发现许多新成分，包括许多具有益生元意义的分子。总的来说，这次调查的结果将帮助我们了解AAPs在表面冰中生存的条件。该项目由美国国家科学基金会天文科学部的“极端环境中的生命”项目资助

0085614YoungAmino acid precursors (AAPs) have been detected on meteorites, in comets, and in theinterstellar medium (ISM). In addition, these precursors (HCN, NH 3 , and CH 3 OH) havebeen irradiated with UV photons in a 10 K water ice matrix to form glycine withoutany aqueous chemistry taking place. Dr. Eliot Young at the Southwest Research Institute will lead a project that will conduct a survey on 16 of the icy bodies in the solar system to look for AAPs. The goal is to assess the distribution of AAPs throughout the icy bodies of the solar system and determine under what conditions AAPs can survive and participate in prebiotic chemistry.Dr. Young expects that this telescopic survey will be more sensitive to the presence of AAPsthan any previous survey. The research team's efforts are concentrated in three areas: 1. Observations at 3 - 5 Mm using NIRSPEC. The 3 - 5 Mm spectral range contains thefundamental transitions of the AAPs. These are an order of magnitude stronger thanthe overtone transitions which have been customarily observed. The breakthrough isNIRSPEC, a 1 - 5 Mm spectrograph on the Keck telescope on Mauna Kea, Hawaii, that will acquire targets as faint as Charon. 2. New Optical Constants: Interpretation of spectral data requires accurate optical constants. The team will generate sample AAP ices under a variety of temperatures and in water and nitrogen host matrices. 3. More Accurate Spectral Modeling: Modifications to a current Hapke code based on the Monte Carlo results will be developed. This will allow more accurate fits to bright ices in which the scattering is non-isotropic and to cases in which the imaginary index is close to 1. This program of observations and analysis is expected to discover many new constituents throughout the solar system, including many molecules with prebiotic significance. Taken as a whole, the results of the survey will help us to understand the conditions in which AAPs can survive in surface ices. This project is funded through the Division of Astronomical Sciences for the NSF's Life in Extreme Environments program.***