利用三维辐射转移模型研究彗星成分、活动性和演化历史

本项目拟将申请人在欧空局彗星探测任务Rosetta/MIRO数据分析工作中建立的三维辐射转移模型应用于更多地面和空间在毫米和亚毫米波段对彗星分子光谱的高精度观测数据分析中，研究彗星彗发成分和结构，精确确定各种气体分子的产生率、相对丰度及太阳辐射的变化，探索不同挥发物的挥发机制；统计和比较分布在太阳系不同区域的彗星的化学成分和活动特点，分析其在形成和演化过程中的共性与特性，揭示不同区域活动性小天体之间的关系；分析具体目标的演化历史，为深入了解太阳系形成机制和演化过程提供线索。本项目的研究内容是行星科学领域的国际热点问题，也是我国未来将要实施主带彗星深空探测任务的直接需求，相应的研究工作将在提高我国彗星研究的观测能力、理论分析能力及在国际上的影响力，增强国际合作交流等方面具有重要的意义。因此，希望得到国家自然科学基金的资助，力争使我国的彗星科学研究列于国际前沿。

In this project, we plan to improve and apply the three-dimension radiation transfer model we built for Rosetta/MIRO data interpretation to analyze more high precession molecular spectra observation data at millimeter/submillimeter of active small bodies in solar system – comets. Based on this 3D model, we aim to investigate the composition and the structure of their coma; to precisely determine production rate, abundance and variation due to heliocentric distance of different volatiles of certain target comet, and to further study the mechanisms and process of sublimation activities on nucleus as well as the role solar insolation plays. Furthermore, we will carry out comparative and statistic study on coma composition and structure of different species of active small bodies. Based on their chemical component and features of activity, we will reveal the generality and specialty during their formation and evolution process to better understand the relationships between comets from different regions. In addition, we will discuss the evolution history of certain individual comets that are highly interested based on theoretical analysis and simulation results, in order to further explore the early evolutional history of our solar system. This research is an international popular problem in planetary science and our works will help to better understand the composition and activity mechanisms of small active bodies. Our result will provide scientific theoretical basis for our country’s small body exploration mission to main belt comet, and will significantly improve our observational abilities, promote international cooperation and enhance our international academic influence on cometary science. Therefore, we want the NSFC to give us the foundation and we will make great effort to make our scientific research level international frontier.