A recent study found that Jupiter was once twice the size that it is now, making it big enough to swallow up 2,000 Earths.

One of the more poignant moments in the movie Star Wars, is when Luke Skywalker gazes wistfully into the sunset on the planet ...

There’s a new object in the distant reaches of our solar system, and it might just offer clues to a long-standing cosmic ...

A few decades ago, the Solar System had nine planets, but in 2006 the International Astronomical ... its potential presence could help solve many astronomical puzzles, including the peculiar ...

Astronomers find evidence of a possible ninth planet beyond Neptune, reigniting the debate about the formation of the Solar ...

PARIS: Astronomers announced on Wednesday they have discovered a massive planet orbiting a tiny star, a bizarre pairing that ...

Jupiter may have once been more than twice its current size, with a magnetic field 50 times stronger, say scientists who ...

HAT-P-1b is one of the 200 or so planets that have been detected outside our Solar System. It has the largest radius ... Several ideas had been proposed solve the puzzle but none seemed to quite fit, ...

Astronomers spotted water around a young, sun-like star for the first time ever, and it could help us understand solar system formation.

Mars' core formed within just a few million years, scientists say compared to the hundreds of millions or even billions of ...

Jupiter, roughly 562 million miles from Earth today, has nearly 100 moons. But Batygin and his collaborator Fred Adams' ...

Play the USA TODAY Daily Crossword Puzzle. Here is everything ... While it's no longer officially a planet, Pluto remains a fascinating and beloved part of our solar system with a slightly less ...