For decades, our solar system was thought to have nine planets, with Pluto considered the smallest and farthest. But in 2006, ...

As a result of the International Astronomical Union’s 2006 demotion of Pluto from planet to dwarf planet, our solar system ...

a yellow dwarf star that contains 99.8% of the solar system's mass. Everything else — from the eight major planets to dwarf planets, comets, asteroids, and icy objects — revolves around it.

But that includes exoplanets, alien worlds that orbit alien suns. Only eight planets call our solar system home. Or there might still be nine if some astronomers are correct about an as-yet ...

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

For instance, Neptune migrated outward, switching places with Uranus, and pushed a lot of the small, icy bodies into the ...

A group of astronomers from across the globe, including a team from the University of Washington and led by Queen's ...

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.

The eight planets in our solar system orbit the sun in roughly the same plane because they all originally formed from the same disc of debris around the sun. The line the sun traces across the ...

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

The eight planets in our solar system orbit the sun in roughly the same plane, because they all originally formed from the same disc of debris around the sun. The line the sun traces across the ...