Comparative Exoplanetology: Ground-Based Observations of the Atmospheres of Transiting Exoplanets

比较系外行星学：凌日系外行星大气的地面观测

• 批准号: 0807992
• 负责人: Seth Redfield
• 金额: $ 31.68万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-01 至 2009-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0807992&HistoricalAwards=false
• 关键词: Comparative; Exoplanetology; Ground; Based; Observations

As the number of detected extrasolar planets continues to rise, a particular subset provides unique opportunities for detailed investigations into the properties of the extrasolar planets themselves. The transmission spectrum of a transiting exoplanet, obtained by the comparison of observations taken in-transit with those taken out-of-transit, can be used to directly measure the effective radius of the exoplanet and its atmosphere or exosphere. Such measurements in strong optical transitions (e.g., Na I, K I) can be used to measure the atmospheric metallicity, rainout of condensates, distribution of stellar flux, and photoionization of atmospheric constituents. Here, Dr. Redfield and his team will build upon their success in detecting the first atmosphere of a transiting exoplanet via transmission spectra. A recently granted large block of survey time on the 9.2-m Hobby Eberly telescope at the McDonald Observatory of the University of Texas at Austin will be used to expand their program to several other bright transiting exoplanets. This large-scale observational program is a major undertaking, and will require a nontrivial commitment to data reduction and analysis. Important issues that must be addressed include the removal of the telluric spectrum, a model of the contribution of differential stellar limb-darkening between the continuum and the cores of stellar lines, and an assessment of the contribution of systematic errors.The main objective of this project is to measure the full optical transmission spectrum for several transiting exoplanets, and enable the first comparative study of exoplanetary atmospheric properties derived from transmission spectra. The resulting observational database will be very rich and will lead to several auxiliary research programs other than transmission spectroscopy, including stellar variability monitoring, reflected light searches, and stellar metallicity measurements.To aid in the dissemination of the results, the McDonald Observatory Education and Public Outreach Office will work with Dr. Redfield to create a series of annual workshops. These workshops will be designed for fifteen secondary school teachers selected from a nationwide applicant pool, and will introduce them to the scientific issues related to extrasolar planets, their atmospheres, and the high spectral resolution observations used to study them. An extensive post-workshop evaluation will also take place in order to assess the effectiveness of the translation of activities developed in the workshop to the classroom.

随着探测到的太阳系外行星的数量不断增加，一个特殊的子集为详细研究太阳系外行星本身的性质提供了独特的机会。凌日系外行星的透射谱是通过比较凌日观测和凌日观测获得的，可以用来直接测量系外行星及其大气层或外圈的有效半径。这种在强光学跃迁(如NaI，KI)中的测量可用于测量大气金属丰度、凝聚体的降雨、恒星通量的分布和大气组分的光致电离。在这里，雷德菲尔德博士和他的团队将在他们通过传输光谱探测凌日系外行星的第一个大气层方面取得成功的基础上再接再厉。最近，得克萨斯大学奥斯汀分校麦克唐纳天文台9.2米长的霍比·埃伯利望远镜获得了一大块调查时间，将用于将他们的计划扩展到其他几颗明亮的凌日系外行星。这项大规模的观测计划是一项重大的任务，需要在数据简化和分析方面做出巨大的承诺。必须解决的重要问题包括消除大地光谱，建立连续带和恒星线核心之间的差异恒星边缘暗化的贡献模型，以及评估系统误差的贡献。该项目的主要目标是测量几颗凌日系外行星的全部光学传输光谱，并能够对由传输光谱得出的系外大气特性进行第一次比较研究。由此产生的观测数据库将非常丰富，并将导致除了透射谱之外的几个辅助研究项目，包括恒星变异性监测、反射光搜索和恒星金属丰度测量。为了帮助传播结果，麦克唐纳天文台教育和公共外联办公室将与雷德菲尔德博士合作，创建一系列年度研讨会。这些讲习班将为从全国申请者库中挑选出来的15名中学教师设计，并将向他们介绍与太阳系外行星、其大气以及用于研究它们的高光谱分辨率观测有关的科学问题。还将进行广泛的讲习班后评价，以评估将讲习班开展的活动翻译到课堂的有效性。