Observing the Atmospheres and Surfaces of Earth Analogs

观察类似地球的大气层和表面

• 批准号: RGPIN-2016-05986
• 负责人: Cowan, Nicolas
• 金额: $ 1.97万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=709838
• 关键词: Observing; Atmospheres; Surfaces; Earth; Analogs

Thousands of planets have been discovered orbiting other stars in recent decades. These worlds are so distant that they appear as unresolved dots in the best of cases, but we can still learn about them based solely on disc-integrated light. Indeed, what they lack in detailed observations, they make up for in quantity and diversity: exoplanets provide us with leverage to crack hard problems in planetary science including atmospheric circulation, cloud formation, and geochemical cycling. The James Webb Space Telescope (JWST) is a 6.5 meter infrared telescope that NASA will launch in fall 2018. It will be the first instrument capable of characterizing the atmospheres of temperate terrestrial exoplanets, and the only telescope capable of measuring their thermal emission until the mid 21st century. Canada is poised to be a leader in the use of JWST for exoplanet observations and my proposed research program will maximize our ability to design, reduce and analyze observations of transiting temperate terrestrials. By working closely with the JWST/NIRISS team at l'Université de Montréal, we will help them design and implement their Guaranteed Time Observations of transiting planets, and my group will be prepared to apply for and analyze Early Release Science, which will become public in 2019. The next flagship after JWST, the Wide Field Infrared Survey Telescope (WFIRST), will be equipped with a coronagraph for imaging nearby planetary systems in reflected light. Even though planets will be unresolved dots in the images, their brightness and color will vary as rotational and orbital motion bring different surface features into view. My group will help determine the measurement precision, time resolution, and spectral resolution necessary to measure planetary obliquity and construct surface maps. The second generation of space-based high-contrast imaging will focus on Earth twins orbiting nearby stars. Exo-cartography will help us understand whether these planets have plate tectonics and volatile cycles like we have on Earth, and will therefore be a key step in establishing the long-term habitability of these worlds.

近几十年来，人们发现了数千颗围绕其他恒星运行的行星。这些世界是如此遥远，以至于在最好的情况下，它们看起来像是未解决的点，但我们仍然可以仅仅基于光盘集成的光来了解它们。事实上，它们在详细观测方面的不足，在数量和多样性上得到了弥补：系外行星为我们提供了解决行星科学难题的杠杆，包括大气环流、云的形成和地球化学循环。 詹姆斯·韦伯太空望远镜（James Webb Space Telescope，JWST）是一个6.5米的红外望远镜，NASA将于2018年秋季发射。这将是第一台能够表征温带类地系外行星大气的仪器，也是唯一一台能够测量其热辐射的望远镜，直到世纪中期。加拿大准备成为使用JWST进行系外行星观测的领导者，我提出的研究计划将最大限度地提高我们设计、减少和分析过境温带陆地观测的能力。通过与蒙特利尔大学的JWST/NIRISS团队密切合作，我们将帮助他们设计和实施对凌日行星的保证时间观测，我的团队将准备申请和分析早期发布科学，该科学将于2019年公开。 JWST之后的下一个旗舰，宽视场红外巡天望远镜（WFIRST），将配备日冕仪，用于在反射光中成像附近的行星系统。 即使行星在图像中是无法分辨的点，它们的亮度和颜色也会随着旋转和轨道运动而变化，从而使不同的表面特征进入视野。 我的小组将帮助确定测量精度，时间分辨率和光谱分辨率，以测量行星的相似性和构建表面地图。 第二代天基高对比度成像将聚焦于围绕附近恒星运行的地球双胞胎。 外星制图将帮助我们了解这些行星是否像我们在地球上一样具有板块构造和波动周期，因此将是建立这些世界长期可居住性的关键一步。