Modelling the performance of the instruments of the Exo-planet characterization satellite Ariel

到目前为止，已经确认的系外行星有3000多颗，还有2000多颗等待确认，还有更多的行星正在进行中(苔丝，乔普斯)和即将到来的(柏拉图)任务。为了真正了解和描述这些行星，将于2028年发射的Ariel卫星将对一组这样的行星进行凌日光谱分析，以确定它们的大气组成。这次欧空局的任务结合了从可见光到中红外波长的两种仪器，较短的波长还具有帮助微调航天器指向的双重目的。它的工作在日地第二拉格朗日点，再加上低温工作和稳定指向的要求，给光谱仪带来了一系列挑战。一个由17个国家组成的国际联盟正在处理这些问题，设计一种卫星有效载荷，该载荷将在四年的任务中对大约1000颗系外行星进行光谱分析。即便如此，对有效载荷性能及其与航天器指向关系的详细建模将是确保一旦发射后能够从Ariel数据中提取最大信息和效率的关键。

To date there are in excess of three thousand confirmed exoplanets and two thousand more awaiting confirmation, with many more to come thanks to ongoing (TESS, CHEOPS) and upcoming (PLATO) missions. To truly understand and characterize these planets, ARIEL, a satellite due to launch in 2028, will perform transit spectroscopy of a set of such planets to establish their atmospheric composition. This ESA mission combines two instruments ranging from the visible to mid-infrared wavelengths, with the shorter wavelengths also having the dual purpose of aiding in fine tuning the spacecraft pointing. Its operation in the Sun-Earth second lagrangian point combined with low temperature operation and stable pointing requirements provide a set of challenges for a spectrometer. These are being addressed by an international consortium of 17 countries, producing a design for a satellite payload which will perform spectroscopy of approximately 1000 exoplanets in a four-year mission. Even so, detailed modelling of the payload performance and its relation to the spacecraft pointing will be key to make sure that maximum information and efficiency can be extracted from the ARIEL data once it is launched.