Eclipse Mapping Exoplanet Atmospheres with the James Webb Space Telescope

使用詹姆斯·韦伯太空望远镜绘制系外行星大气日食图

• 批准号: 2814903
• 金额: --
• 依托单位: University of Bristol
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2814903
• 关键词: Eclipse; Mapping; Exoplanet; Atmospheres; James

Our understanding of exoplanets is significantly lacking in comparison to our understanding of the Solar System planets due to the greater difficulties of observing them. Many properties of exoplanets can be uncovered through the study of their atmospheres, which hold key information on their current state and formation history. The most successful exoplanet detection and characterisation method is the transit method, which allows us access to atmospheric information on the nightside hemisphere of an exoplanet whilst they are in transit and on the dayside hemisphere as they are eclipsed by their host star.My research involves using the technique of eclipse mapping to spatially map the atmospheres of transiting exoplanets. If we take snapshot observations as progressive longitudes of the exoplanet enter eclipse, then we can attribute the reductions in system flux to that region of the planet and construct a 1D emission map of the dayside hemisphere of its atmosphere. If the orbit of the planet is inclined from our viewpoint, then higher latitudes will be eclipsed faster than lower latitudes, allowing us to further sub-attribute the flux reductions to different latitudes, extending our map to 2D. Observing the eclipse at multiple wavelengths then even further allows us to measure the emission from multiple depths of the atmosphere, extending the map to 3D.Hot Jupiters (highly irradiated and tidally locked giant exoplanets with day-scale orbital periods) provide the most exemplary conditions for characterising the atmospheres of exoplanets, owing to their often highly inflated atmospheres which promote strong signals. My research focuses on eclipse mapping the dayside hemisphere of the hot Jupiter WASP-17b using Space Telescope GTO programme 1353 (PI: N.K. Lewis) data obtained by the MIRI/LRS and NIRSpec/G395H instruments onboard JWST. WASP-17b is a prime candidate for these types of observations as the day- to night-side temperature range of its atmosphere spans 1000 - 2500 K, making it likely to host a broad range of spectroscopically active chemical species. It is also an interesting target due to its retrograde orbit, which challenges current planet formation theories - my research aims to contribute to bridging gaps such as this in our understanding of planet formation.This work is undertaken as part of the JWST-TST collaboration, with the aim of combining this dataset and others (three transits and three eclipses, one each respectively obtained by the MIRI/LRS, NIRSpec/G395H, and NIRISS/SOSS instrument onboard JWST, covering the 0.6 - 14 micron wavelength range) to produce the first full 3D map of an exoplanet atmosphere, which will allow us to robustly constrain its thermal, compositional, and dynamical properties, contributing momentously to our understanding of all aspects of exoplanet science. Such techniques will then be extended to other types of exoplanets in order to broaden our understanding of their diversity.

与我们对太阳系行星的理解相比，由于观察它们的困难，我们对系外行星的理解非常缺乏。通过研究其大气，可以发现系外行星的许多特性，这些属性拥有有关其当前状态和形成历史的关键信息。最成功的系外行星的检测和表征方法是运输方法，它使我们可以访问系外行星的夜间半球上的大气信息，而它们在运输中，并且在日子的半球中，因为它们被宿主星星黯然失色。日食映射以在空间上绘制透过系外行星的大气的技术。如果我们将快照观测作为外部球星的进行性纵向的逐步纵向，那么我们可以将系统通量的减少归因于地球的该区域，并构建其大气中半球的一维发射图。如果从我们的角度倾斜行星的轨道，那么较高的纬度将比较低的纬度更快地黯然失色，从而使我们能够进一步将磁通量减少到不同的纬度，从而将我们的地图扩展到2D。在多个波长下观察日食，然后进一步使我们能够测量大气多深度的发射，将地图扩展到3D。热木星（高度辐照和潮汐锁定的巨型巨型外部球队，具有日期尺寸的轨道周期）提供了最典型的条件为了表征系外行星的大气，由于它们通常高度膨胀的大气，从而促进了强烈的信号。我的研究重点是使用太空望远镜WASP-17B的日态映射使用太空望远镜GTO程序1353（PI：N.K. Lewis）数据，该数据由Miri/LRS和NIRSPEC/G395H Instruments获得的数据获得。 WASP-17B是这类观察结果的主要候选者，因为其大气的白天到夜间温度范围跨越1000-2500 K，因此它很可能容纳了广泛的光谱活性化学物种。由于其逆行轨道，这也是一个有趣的目标，它挑战了当前的星球形成理论 - 我的研究旨在在我们对行星形成的理解中造成弥合差距。目的是将该数据集和其他数据集组合（三个过渡和三个日食，每种分别由miri/lrs，NirSpec/g395h和niriss/soss仪器在板上JWST上获得，覆盖0.6-14微米范围），以产生该范围）系外行星大气的第一张完整3D图，这将使我们能够牢固地限制其热，组成和动力学特性，从而有助于我们对系外行星科学各个方面的理解。这样，这些技术将扩展到其他类型的系外行星，以扩大我们对它们多样性的理解。