An international team of astronomers has discovered a distant planetary system that challenges long-standing theories of how ...

Astronomers have found a compact solar system whose planets line up in a way that, according to current models, should not be possible. Around the small star LHS 1903, a dense rocky world orbits on ...

A newly studied solar system breaks the usual planet pattern, raising fresh questions about how rocky and gas planets form.

Since the 1990s, scientists have discovered approximately 6,100 planets outside our solar system, called exoplanets.

A planetary system 116 light-years from Earth has a peculiar pattern. It could flip the script on how planets form, scientists say.

Add Yahoo as a preferred source to see more of our stories on Google. An illustration showing Planet Nine, a hypothetical, undiscovered planet in our solar system. New research now suggests the ...

For decades, our solar system was thought to have nine planets, with Pluto considered the smallest and farthest. But in 2006, Pluto was officially reclassified as a dwarf planet by the International ...

When you see art of our solar system as the planet orbit the sun, you may notice that Earth's orbit has a tilt. It is not a perfect circle. What's more, Earth is not the only planet that displays such ...

Six of the planets of our solar system will be aligned in February for a spectacular sky show. Here’s where and when you can ...