Roche limit Archives

Final semi-major axes of satellites versus their initial orbital distance (in Hill radii) for TRAPPIST-1 e. -- astro-ph.EP

Exoplanets, -moons, -comets, Status Report, TRAPPIST-1

Orbital Stability Of Moons Around The TRAPPIST-1 Planets

by Keith CowingDecember 23, 2025December 23, 2025

We investigate the dynamical stability of potential satellites orbiting the seven planets of the TRAPPIST-1 system using a suite of N-body simulations.

Radial velocity (RV) variations of TOI-6255 b (orange dashed line) measured by KPF (circles) and CARMENES (stars). A Gaussian Process Model (blue dotted line) has been included to remove any stellar activity and instrumental variation on timescales longer than the orbital period of TOI-6255 b. On Nov 24, 2023, we took a set of 21 continuous exposures of TOI6255 with KPF (inset). The resultant RVs followed clearly reveal the 5.7-hour orbit of TOI-6255 b. -- astro-ph.EP

Astrogeology, Astronomy & Telescopes, Exoplanets, -moons, -comets, Gaia - Planetary Perspectives, Habitable Zones, Status Report

An Earth-sized Planet On The Verge Of Tidal Disruption

by Keith CowingAugust 1, 2024August 1, 2024

TOI-6255~b (GJ 4256) is an Earth-sized planet (1.079±0.065 R⊕) with an orbital period of only 5.7 hours. With the newly commissioned Keck Planet Finder (KPF) and CARMENES spectrographs, we determined […]