OF201, the object belongs to the same all-star family as Pluto: dwarf planets. Its diameter, roughly 435 miles (700 km), is ...

Diagrams and animations of planetary orbits are, in a way, lying to you a little bit, ... The sun, Earth, and all of the planets in the solar system orbit around this barycenter.

Cecilia Payne deduced that the sun is mainly made of hydrogen - but was encouraged to downplay her findings by her PhD ...

When is the first day of summer? Find out all the facts about the longest day of the year! When is the first day of summer in ...

For years, astronomers have been searching for a mysterious ninth planet lurking in the dark outer reaches of our solar ...

This explorer spacecraft is heading to a rare asteroid with a naked metal core. It could hold clues to how Earth began ...

There could be a ninth planet in our Solar System after all — and no, it’s not Pluto. Instead, it’s the theoretical Planet X, also called Planet Nine, a wide-orbit planet that would circle the Sun ...

Have you ever wondered why all the planets in our solar system orbit the Sun in roughly the same flat plane? This fascinating phenomenon isn’t a coincidence but a direct result of how our solar ...

For the first time ever, the James Webb Space Telescope (JWST) has captured an unprecedented image of an exoplanet outside ...

Solar System Planets. Astronomy articles on the eight planets, plus the two dwarf planets, Pluto and Eris. Great pictures of everything in the solar system. Updated daily.

For the dwarf planet candidate, one trip around the sun takes over 24,000 years. Its orbit challenges a proposed path for a hypothetical Planet Nine.

Bad news, earthlings. Computer simulations of the solar system’s future reveal a new risk facing us all: The gravitational tug of a passing star could either cause another planet to smack into ...