地球与行星天体物理

We report the discovery of a low-mass transiting brown dwarf orbiting TOI-6884 (TIC~156514476, $T_{\rm mag}=11.4$) from NASA's \textit{Transiting Exoplanet Survey Satellite} (\textit{TESS}) mission. The \textit{TESS} light curves initially…

We explore the impact of spectral interpolation in radial velocity (RV) time-series extracted through template-based methods. We build synthetic datasets with Gaussian profiles to evaluate flux residuals and line asymmetry that are a result…

Independent analysis of individual spectral lines, or line-by-line (LBL) analyses, can improve upon standard cross-correlation function (CCF) methods for measuring radial velocities (RVs) because they preserve critical information about…

The giant planets, Jupiter, Saturn, Uranus, and Neptune, all have vibrant and dynamic atmospheres. The iconic belt--zone structure of Jupiter, together with the Great Red Spot, is instantly recognizable. Saturn, with its dramatic ring…

We introduce the maximum-initial-mass problem as a standalone optimal-control formulation for low-thrust trajectory design and analyze its structure within Pontryagin's framework. For fixed transfer time and final state, the formulation…

The astrometric measurements provided by the Gaia space mission represent a key advancement in the search and characterization of exoplanets, helping in particular to solve the mass degeneracy intrinsic to the radial velocity (RV) method.…

Escaping from the Earth is the first step of interplanetary transfers. Traditional ballistic escape trajectories in the Sun-Earth circular restricted three-body problem face limitations in relatively long time of flight and low hyperbolic…

Understanding how solid material in planet-forming disks evolves from micron-sized dust to planetary cores is a central challenge in modern astrophysics. This study has advanced dramatically in the past decade, largely driven by ALMA and…

We analyze KMT-2025-BLG-2093, with angular Einstein radius $\theta_{\rm E}=13.1\pm 2.8\,\mu{\rm as}$, which makes it the second isolated microlens that lies in the ``Einstein Desert'' ($9\,\mu{\rm as}<\theta_{\rm E}<25\,\mu{\rm as}$)…

We present the first spectroscopic mineralogical analysis of the dust coma of an interstellar object (ISO) from JWST mid-infrared spectroscopy of 3I/ATLAS (3I). 3I exhibits a strong 10-micron emissivity feature commonly seen on asteroids,…

We present JWST/MIRI spectroscopy of 14 disks in the older (~5-10 Myr) Upper Scorpius (USco) association and use slab of gas in local thermal equilibrium to infer basic gas properties. We find that half of these disks are molecular rich,…

Tracing the chemical evolution of protoplanetary disks over time requires observations of disks at different ages. However, most JWST/MIRI surveys published to date have targeted younger ($\sim$1-3 Myr) rather than older systems. We present…

Determining the relative contributions of cometary and asteroidal sources to the sporadic meteoroid population remains a longstanding challenge, particularly because commonly used orbit-based classification criteria have not been rigorously…

Circumbinary discs are observed to develop central cavities carved by the gravitational influence of the binary. Analytical estimates of cavity sizes predict truncation at $\sim 2 \textrm{--} 3$ binary separations, depending on the binary…

This paper presents solarsystem, a validated lightweight and dependency-free Python package for planetary positions and solar-lunar event calculations. The package provides heliocentric and geocentric positions for the major planets,…

The 14 Herculis system hosts two super-Jupiters on eccentric, significantly misaligned orbits. This orbital architecture represents a dynamical puzzle that demands explanation. In this work, we reproduce the system's dynamical history and…

Sub-Neptunes and Neptunes are often modeled with distinct, fully convective layers. Yet, there are several arguments for compositions gradients that can inhibit convection. In these regions, energy transport depends on the thermal…

Here we present an updated shape model of (486958) Arrokoth, the bilobate Kuiper Belt Object (KBO) which the NASA New Horizons spacecraft flew past in 2019. This updated shape model uses all of the resolved images of Arrokoth obtained by…

The Atacama Large (sub-)millimeter Array (ALMA) has been in scientific operations for almost 15 years. We celebrate this achievement by providing a summary of the ``Disks and planet formation'' scientific category, with an emphasis on the…

The streaming instability is the leading model for planetesimal formation in protoplanetary disks, but it typically operates within the first ~Myr. In the Solar System, however, some planetesimals (the chondrite parent bodies) formed 2-4…