Astronomers using the James Webb Space Telescope have detected possible signs of gases released by volcanic activity on a ...

Today, we know of more than 5,000 exoplanets: planets outside our solar system that orbit other stars. While the effort to ...

Ever since NASA's New Horizons sent back the first-ever photos of Pluto in 2015, the dwarf planet's mysterious heart ... roughly the size of Arizona from north to south. Pluto was discovered ...

Scientists have found two new habitable planets, nearly 8 times the size of Earth, that don’t orbit a ‘Goldilocks’ star. These are the closest candidates to Earth to support human life on ...

At just 16 feet across, that one is about the size of a typical SUV. Its closest approach will happen 184,000 miles from the planet.

Four "potentially hazardous" space rocks, which are between 100 and 580 feet across, will all make their closest approaches to Earth within less than 12 hours of one another on Thursday (Oct. 24). Two ...

In 1992 astronomers reported the first planet-size masses around a dead star, the pulsar PSR1257+12, which sits 2,000 light-years away. Three years later came news of the first known exoplanet ...

Asteroids are rocky objects that orbit the Sun, just like planets do. There are millions of asteroids of very different shapes and sizes. Some are almost spheres, like planets, but most are ...