New evidence shows that, far beyond Pluto, there may exist a hypothetical planet referred to as Planet X or Planet Nine.

In 1949, famed mathematician and physicist John von Neumann delivered a series of addresses at the University of Illinois, ...

Having made its closest approach to the sun on Wednesday October 29, comet 3I/ATLAS will soon be visible from Earth ...

Discover what could happen if Planet X entered our solar system unexpectedly. Government shutdown reaches its 40th day as ...

There are no confirmed exomoons, moons orbiting distant exoplanets in other solar systems. There are a few candidates, but ...

A distant gas giant the size of 10 Jupiters is now the first planet outside Earth's solar system to be mapped in three ...

Comet 3I/ATLAS has gone from being an astronomic curiosity to the darling of the entire space science community. It is the ...

Water isn't just delivered to planets by comets and asteroids — it can also be forged as worlds form, a new study finds.

Newly discovered comet C/2025 V1 (Borisov), which has some minor similarities to 3I/ATLAS, will make its closest approach to ...

As telescopes have become more powerful, it’s turned out our solar system is not the only game in town: There are millions of ...

A newly discovered warp in the outer Solar System may have been created by a small, rocky world, much closer to the Sun than ...

“If you build a map at a wavelength that water absorbs, you’ll see the water deck in the atmosphere, whereas a wavelength ...