地球与行星天体物理
We present the first prediction for the mass distribution function of Galactic free-floating planets (FFPs) that aims to accurately include the relative contributions of multiple formation pathways and stellar populations. We derive our…
One of the big challenges in exoplanet science is to determine the atmospheric makeup of extrasolar planets, and to find biosignatures that hint at the existence of biochemical processes on another world. The biomarkers we are trying to…
According to models such as panspermia or the Nebula-Relay hypothesis, the ancestors of life on Earth once lived in molecular clouds. Then what are the energy source and bioenergetics for such lifeforms? In this paper, we propose a new…
Named for orbital kinship with Pluto, the Plutinos are a prominent group of Kuiper Belt objects whose orbital periods are in libration about the 3/2 ratio with Neptune's. We investigate the long term orbital dynamics of known Plutinos, with…
As the number of potential exomoon candidates grows, there is a heightened motivation of pursing orbital stability analyses. In this work, we provide an in-depth investigation into 4-body systems, consisting of a star, planet, moon, and…
Eccentric planets may spend a significant portion of their orbits at large distances from their host stars, where low temperatures can cause atmospheric CO2 to condense out onto the surface, similar to the polar ice caps on Mars. The…
Exoplanets are detected around stars of different ages and birthplaces within the Galaxy. The aim of this work is to infer the Galactic birth radii ($r_\text{birth}$) of stars and, consequently, their planets, with the ultimate goal of…
Astrophysical discs which are sufficiently massive and cool are linearly unstable to the formation of axisymmetric structures. In practice, linearly stable discs of surface density slightly below the threshold needed for this instability…
Ground-based near-IR observations have revealed that Uranus anomalously hot upper atmosphere, detected by Voyager 2, has been steadily cooling. The observed $H_3^+$ and $H_2$ emission-line spectra probe Uranus' ionosphere and thermosphere,…
We investigate Gravity Waves (GWs) in the lower atmosphere of Mars based on pressure timeseries acquired by the InSight lander. We compile a climatology showing that most GW activity detected at the InSight landing site takes place after…
Recent advances have enabled the discovery of a population of potentially Earth-like planets, yet their orbital eccentricity, which governs their climate and provides clues about their origin and dynamical history, is still largely…
Organic macromolecular matter is the dominant carrier of volatile elements such as carbon, nitrogen, and noble gases in chondrites -- the rocky building blocks from which Earth formed. How this macromolecular substance formed in space is…
Absolute astrometry with Gaia is expected to detect and characterize the orbits of thousands of exoplanets in the coming years. A tool, GaiaPMEX, was recently developed to characterize multiple systems based on Gaia-only data, and, when…
[Abridged] Gas kinematics is a new and unique way to study planet-forming environments by an accurate characterization of disk velocity fields. High angular resolution ALMA observations allow deep kinematical analysis of disks, by observing…
Over the past decade, observations of evaporating exoplanets have become increasingly common, driven by the discovery of the near-infrared helium-triplet line as a powerful probe of atmospheric escape. This process significantly influences…
Exoplanets on close-in orbit are subject to intense X-ray and ultraviolet (XUV) irradiation from their star. Their atmosphere therefore heats up, sometimes to the point where it thermally escapes from the gravitational potential of the…
Numerical N-body simulations are commonly used to explore stability regions around exoplanets, offering insights into the possible existence of satellites and ring systems. This study aims to utilize Machine Learning (ML) techniques to…
We examine images of the protoplanetary disk 114--426 with JWST/NIRCam in 12 bands. This large disk is oriented edge-on with a dark midplane flanked by lobes of scattered light. The outer edges of the midplane are seen in silhouette against…
We search for radio emission from star-planet interactions in the M-dwarf system GJ~486, which hosts an Earth-like planet. We observed the GJ~486 system with the upgraded Giant Metrewave Radio Telescope (uGMRT) from 550 to 750 MHz in nine…
Spokes are localized clouds of fine particles that appear over the outer part of Saturn's B ring. Over the course of the Cassini Mission, the Imaging Science Subsystem (ISS) obtained over 20,000 images of the outer B ring, providing the…