Planetary Science

Comets don’t just orbit our sun. “Exocomets” are common around other stars in the galaxy, too

New work pinpoints the origins of the planet Theia, whose ancient collision with Earth likely produced the moon

A machine-learning breakthrough could lift the veil on Earth’s early history—and supercharge the search for alien life

NASA spent years and billions of dollars collecting Martian samples to bring home. Now they might be stranded

Former NASA officials warn that the U.S. looks poised to lose its self-declared race to beat China to the moon

The planet’s brightness is dimming—changing rainfall, circulation and temperature

Data from the James Webb Space Telescope and other observatories suggests a supervolcanic exomoon may lurk around the giant exoplanet WASP-39b

A fresh analysis of old data has found rich organic chemistry within the hidden ocean of Saturn’s moon Enceladus

The Habitable Worlds Observatory is poised to tell us whether Earth-like planets are common—if it can get off the ground

Many asteroids are related, but their family trees can be hard to trace

Lunar minerals can rust when bombarded with high-energy oxygen particles, experiments show

Hot, small and old—exoplanet TOI-561 b is just about the worst place to look for alien air. Scientists using JWST found it there anyway