A new study suggests yet another theory for a possible extra planet in our solar system, likely of a size between Mercury and ...

We all need some space sometimes—but it's harder to find than you might think. How far into our universe do we have to go to ...

Exoplanet hunters Christopher Watson and Annelies Mortier explain the long search for a 'twin Earth' capable of sustaining ...

"Though our Mars orbiters continue to make impressive contributions to Mars science, it's always extra exciting to see them ...

A recent study introduces the idea of Planet Y, a theoretical world that could explain strange gravitational behavior beyond ...

Astrophysicist and author Neil deGrasse Tyson explains the theory behind the growing evidence about a possible hidden planet ...

Astronomers have observed a massive growth rate in a free-floating rogue planet that’s gobbling up gas and dust at a record rate of 6.6 billion tons per second.

Changing how the world eats could reduce premature deaths, save trillions of dollars and slow the impacts of climate change, ...