地球与行星天体物理
Brown dwarfs with known physical properties (e.g., age and mass) are essential for constraining models of the formation and evolution of substellar objects. We present new high-contrast imaging observations of the circumbinary brown dwarf…
The Wide Field Camera 3 (WFC3) instrument on the Hubble Space Telescope has provided an abundance of exoplanet spectra over the years. These spectra have enabled analysis studies using atmospheric retrievals to constrain the properties of…
The Hilda population of asteroids is located in a large orbital zone of long-term stability associated with the Jupiter J3/2 mean motion resonance. They are a sister population of the Jupiter Trojans, since both of them are likely made up…
One of the most prolific methods of studying exoplanet atmospheres is transmission spectroscopy, which measures the difference between the depth of an exoplanet's transit signal at various wavelengths and attempts to correlate the depth…
Cislunar space is the volume between Earth's geosynchronous orbit and beyond the Moon, including the lunar Lagrange points. Understanding the stability of orbits within this space is crucial for the successful planning and execution of…
We present the first transmission spectroscopy study of an exoplanet atmosphere with the high-resolution mode of the new Gemini High-resolution Optical SpecTrograph (GHOST) instrument at the Gemini South Observatory. We observed one transit…
TOI-836 is a ~2-3 Gyr K dwarf with an inner super Earth ($R=1.7 R_\oplus$, $P=3.8$ d) and an outer mini Neptune ($R=2.6 R_\oplus$, $P=8.6$ d). JWST/NIRSpec 2.8--5.2 $\mu$m transmission spectra are flat for both planets. We present…
The main challenge of exoplanet high-contrast imaging (HCI) is to separate the signal of exoplanets from their host stars, which are many orders of magnitude brighter. HCI for ground-based observations is further exacerbated by speckle…
A significant fraction of hot Jupiters have orbital axes misaligned with their host stars' spin axes. The large stellar obliquities of these giants have long been considered potential signatures of high-eccentricity migration, which is…
We explore whether hyperbolic diffusion may help explain sharp edges in the gaps in Saturn's rings. Sharp edges are conventionally understood to be due to angular momentum flux reversal at gap edges. We do not dispute this finding, but…
Recently, Seligman et. al. (2024) identified a population of near-Earth objects (NEOs) that exhibit statistically significant non-gravitational accelerations with no coma, and labeled them dark comets. Here, we show that one of these…
We present new Atacama Large Millimeter/submillimeter Array observations that, for the first time, detect hydrogen and helium radio recombination lines from a protoplanetary disk. We imaged the Orion Nebula Cluster at 3.1 mm with a spectral…
The collision outcomes of dust aggregates in protoplanetary disks dictate how planetesimals form. Experimental and numerical studies have suggested that bouncing collisions occurring at low impact velocities may limit aggregate growth in…
Atmospheric compositions preserve the history of planet formation processes. Jupiter has the remarkable feature of being uniformly enriched in various elements compared to the Sun, including highly volatile elements such as nitrogen and…
Light-matter interactions lie at the heart of our exploration of exoplanetary atmospheres. Interpreting data obtained by remote sensing is enabled by meticulous, time- and resource-consuming work aiming at deepening our understanding of…
The origin of Mercury still remains poorly understood compared to the other rocky planets of the Solar System. One of the most relevant constraints that any formation model has to fulfill refers to its internal structure, with a predominant…
A proposed Vera C. Rubin Observatory Deep Drilling micro-survey of the Kuiper Belt will investigate key properties of the distant solar system. Utilizing 30 hours of Rubin time across six 5-hour visits over one year starting in summer 2026,…
The Convective Overstability (COS) is a hydrodynamic instability occurring in protoplanetary disk (PPD) regions with an adverse radial entropy gradient. It is a potential driver of turbulence and may influence planetesimal formation. In…
Context. Transition disks (TDs) are a type of protoplanetary disk characterized by a central dust and gas cavity. The processes behind how these cavities are formed and maintained, along with their observed high accretion rates of $10^{-8}…
Saturn raises a time-dependent tide on its small moon Enceladus, due to the eccentricity of the orbit. As shown in a companion paper (Goldreich et al.), the resulting tidal heating drives Enceladus into a limit cycle, in which its…