When I was a kid, there were nine planets. Now we know of thousands! But that includes exoplanets, alien worlds that orbit alien suns. Only eight planets call our solar system home. Or there might ...

Astronomers have spent the past decade cataloguing thousands of planets beyond the solar system, many of them falling into a ...

A new study has proposed the existence of Planet Y, an alternative Planet Nine candidate that is smaller and closer to Earth than the hypothetical Planet X, which astronomers have been hunting for ...

The odd atmosphere of a fledgling exoplanet is causing astronomers to question leading theories of how planets form. When you purchase through links on our site, we may earn an affiliate commission.