The solar system is composed of the sun, eight major planets, five dwarf planets, over a hundred moons, and countless comets ...

On August 24, 2006, our solar system lost a planet. It wasn't by cataclysmic destruction, but rather by the vote of the International Astronomical Union, which declared that Pluto, considered the ...

Siraj’s Planet Y search started about a year ago when he was trying to find out whether the shape of the Kuiper Belt is flat.

The shocking findings were part of a recent study in which astronomers effectively peered back in time to discover what Jupiter was like in its early years. Jupiter is not only the largest in the ...

Pluto was reclassified as a dwarf planet in 2006. Our solar system may have a ninth planet after all, researchers say. The possibility that an additional planet may be hidden far into the solar system ...