The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define ...

For decades, Pluto was celebrated as the ninth planet of our solar system. However, in 2006, the International Astronomical ...

Scientists using data from the European Space Agency’s Gaia mission have made a groundbreaking discovery: a massive exoplanet ...

Filmmaker Adam Nemoy helps celebrate the 90th anniversary of Pluto's discovery this month at the 6th annual 'I Heart Pluto' ...

A U.S. scientist searching for a civilization across 7 Earth clones circling the red dwarf star TRAPPIST-1 says its own alien ...

With an assist from the NEID spectrograph, a team of astronomers have confirmed the existence of exoplanet Gaia-4b—one of the ...

Charon is the largest moon of the dwarf planet Pluto ... Whereas a moon usually orbits a planet, both Pluto and Charon orbit a point in space between them — their common center of mass.

An object eight times the mass of Jupiter may have swooped around the sun, coming superclose to Mars' present-day orbit ...

Astronomers have found two planets around two separate stars that are succumbing to their stars' intense heat.

Beautiful photos of the six planets aligned in the night sky have emerged online. Mars, Jupiter, Uranus, Neptune, Venus and Saturn are all currently lined up in a row and will be visible in the night ...

Scientists studying samples that NASA collected from the asteroid Bennu found a wide assortment of organic molecules that ...