SubNeptunes - Probing Exoplanetary Atmospheres in the Sub-Neptune Regime

海王星下 - 探测海王星下的系外行星大气层

基本信息

批准号：
EP/X025179/1
负责人：
Nikku Madhusudhan
金额：
$ 232.32万
依托单位：
University of Cambridge
依托单位国家：
英国
项目类别：
Research Grant
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=EP%2FX025179%2F1
关键词：
SubNeptunes Probing Exoplanetary Atmospheres Sub

项目摘要

Sub-Neptune planets represent the new frontier in exoplanet science. Exoplanet demographics reveal that planets between Earth and Neptune in size (1-4 Earth radii) overwhelmingly dominate the known exoplanet population. These planets, collectively referred to as "sub-Neptunes", encompass the entire range of planet types from rocky super-Earths to volatile-rich mini-Neptunes. These planets dominate the exoplanet population but have no analog in the solar system. A defining feature of this population is the "Radius Valley", a bimodal distribution in radii with two peaks separated by a valley around 1.8 Earth radii. As competing theories of planet formation, interiors and atmospheres strive to understand this exotic regime, it is becoming clear that atmospheric observations are essential to place definitive constraints on their properties, physical processes and origins. We propose to conduct a comprehensive atmospheric survey of ten nearby sub-Neptunes across the Radius Valley. The project will address three fundamental questions in exoplanetary science: How diverse are the atmospheric compositions of sub-Neptunes? How do disequilibrium processes operate in sub-Neptune atmospheres? How do sub-Neptunes form and evolve? These questions will be answered using a combination of pioneering approved observations with state-of-the-art facilities in space (HST and JWST) and on ground, and key advancements in theoretical modelling and atmospheric retrieval techniques. This will enable new detections of key molecular species such as H2O, CH4, NH3, and HCN in diverse planets across the radius valley and key constraints on physical and chemical processes in the atmospheres and on their formation conditions. In addition to answering the above transformational questions, we will conduct an in-depth atmospheric characterisation of a habitable-zone sub-Neptune using approved JWST observations.

亚北极线行星代表系外行星科学领域的新边界。系外行星人口统计学表明，地球和海王星之间的行星的大小（1-4地球半径）绝大多数主导已知的系外行星种群。这些行星统称为“亚北极子”，涵盖了从岩石的超产星到富含挥发性富含挥发性的迷你纽扣的整个行星类型范围。这些行星占主导地位的系外行星，但在太阳系中没有类似物。该人群的一个定义特征是“半径谷”，这是半径中的双峰分布，两个峰在1.8地球半径附近被一个山谷隔开。随着行星形成的竞争理论，内部和气氛努力理解这种异国情调的政权，很明显，大气观察对于对其性质，物理过程和起源的确定性约束至关重要。我们建议对整个半径山谷的十个附近的亚北极群进行全面的大气调查。该项目将解决系外行星科学方面的三个基本问题：子纳普的大气组成有多多样化？不平衡过程如何在亚新播放大气中运作？子纳普如何形成和进化？这些问题将通过开创性批准的观察与最先进的设施（HST和JWST）以及地面上的最新设施以及理论建模和大气检索技术的关键进步来回答这些问题。这将使在整个半径山谷的不同行星中的H2O，CH4，NH3和HCN等关键分子物种的新检测以及对大气及其形成条件下物理和化学过程的关键限制。除了回答上述变革性问题外，我们还将使用认可的JWST观测值对可居住区域的近路进行深入的大气表征。

项目成果

期刊论文数量（2）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Possible Hycean conditions in the sub-Neptune TOI-270 d

DOI：
10.1051/0004-6361/202348238
发表时间：
2024-03
期刊：
Astronomy & Astrophysics
影响因子：
0
作者：
M. Holmberg;N. Madhusudhan
通讯作者：
M. Holmberg;N. Madhusudhan

Carbon-bearing Molecules in a Possible Hycean Atmosphere

DOI：
10.3847/2041-8213/acf577
发表时间：
2023-09
期刊：
The Astrophysical Journal Letters
影响因子：
0
作者：
N. Madhusudhan;Subhajit Sarkar;Savvas Constantinou;Måns Holmberg;Anjali A. A. Piette-Anjali-A.-A.-Piette-49809422;Julianne I. Moses
通讯作者：
N. Madhusudhan;Subhajit Sarkar;Savvas Constantinou;Måns Holmberg;Anjali A. A. Piette-Anjali-A.-A.-Piette-49809422;Julianne I. Moses