Planets

Data compiled from NASA's Juno mission shows that Europa, Jupiter's ice-covered moon, severely lacks oxygen.

The researchers who originally proposed the Planet Nine hypothesis have narrowed down where the giant elusive world might be hiding, after carrying out an exhaustive sweep of the theoretical planet's orbital pathway.

Traveling to Mars will involve close quarters for more than two years. Here's how astronauts can deal with the stress of those conditions.

A distant star system housing 6 planets that move in 'mathematically perfect' orbits has ignited a search for possible alien technosignatures.

New radar images show surprise changes to the doomed ERS-2 spacecraft as it tumbled through Earth's atmosphere on Feb. 21.

The International Astronomical Union has confirmed the existence of three currently unnamed moons — one around Uranus and two orbiting Neptune.

Data collected by the James Webb Space Telescope shows that, like Pluto, the dwarf planets Eris and Makemake could be geologically active, which changes what we know about their chances of harboring life.

On Feb. 22, Venus and Mars will look like a cosmic colon as they appear side by side in the predawn sky.

Last week, the Martian moon Phobos passed neatly between Mars and the sun. NASA's Perseverance rover caught the fortuitous eclipse on camera.

A new study of Saturn's 'Death Star' moon Mimas finds evidence of a young, underground ocean that may be hospitable to early forms of life.