Origin of volatiles and organics on Earth, IDPs, meteorites, and comets

最有趣的科学问题之一是了解我们的行星系统诞生的条件，以及建立一个宜居地球所必需的条件。要回答这些问题，我们必须首先了解早期太阳星云中生命的关键成分——水、含碳化合物和含氮化合物——的演化、径向分布和丰度，它们以什么形式存在，以及它们是如何被运送到地球的。这个古老时代的物理条件和化学复杂性的重要线索隐藏在地球表面挥发物和太阳系原始天体（如陨石、彗星和行星际尘埃粒子）的化学和同位素组成中。除非使用可行的太阳星云演化模型，否则将实验室调查揭示的矿物学、化学、同位素组成和水含量与大约4.57 Ga前年轻太阳系的条件联系起来是具有挑战性的。因此，在接下来的三年里，我们将创建一个改进的太阳星云模型，包括气体和尘埃的温度和密度演化、传输和气体颗粒随时间变化的同位素分馏化学。我们的主要研究方向是：1)水和主要含C、O、n分子在早期太阳星云中的分布和演化；2)在整个早期太阳星云（特别是行星形成区）中，水和挥发性和难熔物质的C-、O-和n -同位素组成的来源。

One of the most intriguing scientific questions is to understand conditions at which our planetary system was born and the conditions necessary for building a habitable Earth. To answer these questions, one has to first understand the evolution, radial distribution, and abundances of the key ingredients for life - water, carbon-, and nitrogen-bearing compounds in the early solar nebula, in what form they existed, and how they have been delivered to Earth. The important clues to the physical conditions and chemical complexity in this ancient epoch are hidden in the chemical and isotopic composition of Earth surface volatiles and primitive bodies of the solar system such as meteorites, comets, and interplanetary dust particles. It is challenging to relate the mineralogical, chemical, and isotopic composition and water content revealed by laboratory investigations with the conditions in the young solar system at about 4.57 Ga ago, unless a feasible evolutionary model of the solar nebula is used. Therefore, in the next three year we will create an improved model of the solar nebula that includes gas and dust temperature and density evolution, transport, and gas-grain time-dependent chemistry with isotopic fractionation. The main directions of our research will be: 1) distribution and evolution of water and major C-, O-, and N-bearing molecules throughout the early solar nebula; 2) origin of water and C-, O-, and N-isotopic composition of volatile and refractory material throughout the early solar nebula (in particular, planet-forming zone).