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

The six planets will be visible in the days immediately leading up to Jan. 21, and for about four weeks afterward. Mars, ...

Arrokoth is composed of two separate bodies, 3 and 9 miles across. In the distant past they rotated so slowly about each other that their mutual gravitational attraction caused them to come together ...

Astronomers using the James Webb Space Telescope (JWST) have uncovered a planet so extraordinary it has defied all existing ...

The James Webb Space Telescope has provided groundbreaking insights into a new type of exoplanet, fundamentally different ...

Plate tectonics give Earth its mountains, earthquakes, continental drift and maybe even helped give rise to life itself. But ...

This January, the night sky is putting on a show like no other. A rare parade of six planets will align, creating a celestial ...

Astrophysicists have imaged a large number of exocomet belts around nearby stars, and the tiny pebbles within them. The crystal-clear images show light being emitted from these millimeter-sized ...

"The rate at which the planet is evaporating is utterly cataclysmic, and we are incredibly lucky to be witnessing the final hours of this dying planet." ...

Alignments of five or more planets are rare—there will be two more featuring five or more planets this year, but after that ...

Mars's atmosphere and climate are impacted by interactions with solar wind, a stream of plasma comprised of protons and ...

Mars is known as the 'Red Planet.' Learn about its reddish hue, caused by iron oxide, its position as the fourth planet from ...