Rocky planets hosted by close-in extrasolar systems are likely to be tidally locked in 1:1 spin-orbit resonance, a configuration where they exhibit permanent dayside and nightside. Because of the resulting day-night temperature gradient, the climate and large-scale circulation of these planets are strongly determined by their atmospheric stability against collapse, which designates the runaway condensation of greenhouse gases. To better constrain the surface conditions of rocky planets located in the habitable zone of their host star, it is therefore crucial to elucidate the mechanisms that govern the day-night heat redistribution. As a first attempt to bridge the gap between multiple modelling approaches ranging from idealised models to 3-D General Circulation Models (GCM), we developed a General Circulation Meta-Model (GCMM) able to reproduce both the closed-form solutions provided by analytical models and the numerical solutions obtained from GCM simulations. We used this approach to characterise the atmospheric stability of Earth-sized rocky planets with dry atmospheres containing CO2, and we benchmarked it against 3-D GCM simulations using THOR GCM. We observe that the collapse pressure below which collapse occurs can vary by ~40% around the value predicted by analytical scaling laws depending on the mechanisms taken into account among radiative transfer, atmospheric dynamics, and turbulent diffusion. Particularly, we find (i) that the turbulent diffusion taking place in the dayside planetary boundary layer (PBL) globally tends to warm up the nightside surface hemisphere except in the transition zone between optically thin and optically thick regimes, (ii) that the PBL also significantly affects the day-night advection timescale, and (iii) that the slow rotator approximation holds from the moment that the normalised equatorial Rossby deformation radius is greater than 2.
Most super-Earths formed by dry pebble accretion are less massive than 5 Earth masses
我们从自洽的尘埃增长模型研究了岩石行星的形成。特别是，我们的目标是计算一个岩石行星的最大核心质量，可以维持一个薄的H-He大气，以解释开普勒的大小分布的第二个峰值。我们通过冰线内的卵石吸积来模拟行星的生长。卵石通量计算自洽尘埃生长通过求解对流扩散方程为代表的灰尘大小。包括粉尘在水冰线上的凝结、漂移、破碎和升华。光盘的演变计算$α$光盘从中央恒星的光蒸发。行星是从一个月球质量的胚胎中通过硅酸盐卵石的吸积和气体的吸积而成长起来的。我们分析了不同初始椎间盘质量、$α$粘度、椎间盘金属含量和胚胎位置的影响。最后，我们计算了由于蒸发造成的大气质量损失。我们发现，在冰线内，破碎屏障决定了卵石的大小，这导致不同的圆盘粘度不同的行星生长模式。在冰线内的卵石隔离质量通常衰减到低于5 M $_{\oplus}$的值在第一个百万年的磁盘演变，限制核心群众的价值。在计算了大气质量损失后，我们发现核心在$\sim$ 4 M $_{\oplus}$以下的行星大气层被完全剥离，少数4-5 M $_{\oplus}$核心保留着稀薄的大气层，使它们处于开普勒尺寸分布的间隙/第二峰值。总的来说，我们发现岩石行星只在低粘度盘（$α\lesssim 10^{-4}$）中形成。当$α\geq 10^{-3}$时，岩石天体不会超过火星质量。干卵石吸积最典型的结果是质量从火星到$\sim$ 4 M $_{\oplus}$的类地…
On the influence of equilibrium tides on transit-timing variations of close-in super-Earths. I. Application to single-planet systems and the case of K2-265 b
Sensitivity of Dry Lava Planet Atmospheric Emission Spectra to Changes in Lava Compositions
Leiden Observatory, Leiden University（莱顿天文台，莱顿大学）；Department of Earth Sciences, Vrije Universiteit Amsterdam（地球科学系，阿姆斯特丹自由大学）；Astrophysics Research Institute, Liverpool John Moores University（天体物理研究所，利物浦约翰摩尔斯大学）；SRON Netherlands Institute for Space Research（荷兰空间研究研究所）；Center for Astrophysics, Harvard & Smithsonian（天体物理中心，哈佛大学与史密森尼学会）
High Tide or Riptide on the Cosmic Shoreline? A Water-Rich Atmosphere or Stellar Contamination for the Warm Super-Earth GJ~486b from JWST Observations
University of Arizona（亚利桑那大学）；Johns Hopkins APL（约翰斯·霍普金斯大学应用物理实验室）；Johns Hopkins University（约翰斯·霍普金斯大学）；University of Michigan（密歇根大学）；Imperial College London（伦敦帝国学院）；University of Maryland, Baltimore County（马里兰大学巴尔的摩县分校）；NASA Goddard Space Flight Center（美国国家航空航天局戈达德太空飞行中心）
Habitability of Tidally Heated H$_2$-Dominated Exomoons around Free-Floating Planets
Ludwig-Maximilians-Universität München（慕尼黑大学）；Max-Planck-Institut für extraterrestrische Physik（马克斯·普朗克地外物理研究所）；Exzellenzcluster ‘Origins’（起源卓越集群）；European Space Agency (ESA)（欧洲空间局）；European Space Astronomy Centre (ESAC)（欧洲空间天文中心）；European Southern Observatory（欧洲南方天文台）
