super-Mercury Archives - Astrobiology

Artist’s conception of the K2-360 system, showing the ultra-dense super-Earth K2-360 b (red) in its extremely close orbit around its Sun-like star, with the more distant companion K2-360 c (blue) in the background. The scorching temperatures on K2-360 b, which completes an orbit in just 21 hours, likely result in a molten or partially molten surface. Credit Astrobiology Center

Ultra-dense Super-Earth With An Outer Companion Offers Clues About Its Formation

by Keith CowingNovember 25, 2024September 18, 2025

An international team led by researchers in Japan and Europe has discovered a new multi-planet system around a Sun-like star, including an ultra-short period planet with one of the highest […]

Planet radius vs. mass for our sample (diamonds) are shown in the context of the rocky planet population (circles). Opaque diamonds represent our mass and radius measurements while translucent diamonds are the previously published values. Lines show mass-radius relations for planets with an Earth-like composition, a purely silicate-rock composition, and a purely iron composition (Zeng et al. 2019). Literature values come from the NASA Exoplanet Archive (Akeson et al. 2013) queried 4/12/2024 for planets with mass and radius measurements with fractional uncertainties

Astrogeology, Exoplanets, -moons, -comets, Status Report, Stellar Cartography

The Compositions of Rocky Planets in Close-in Orbits Tend to be Earth-Like

by Keith CowingOctober 2, 2024

Hundreds of exoplanets between 1-1.8 times the size of the Earth have been discovered on close in orbits. However, these planets show such a diversity in densities that some appear […]