A powerful new observatory is the best hope yet for finding the elusive Planet 9, a large planet that some scientists say is ...

It's rare for any observatory to directly image a planet beyond our solar system, called an exoplanet, but the powerful James Webb Space Telescope has captured four of them in the stellar system HR ...

We've known for over 30 years that there are other stellar systems in our galaxy, but we don't have any idea how many there are.

Pluto isn’t the only dwarf planet in our solar system's outer reaches. Now is an ideal time to look for the egg-shaped Haumea, says Abigail Beall ...

Anyone who looked up at the sky on Wednesday night may have caught a glimpse of an impressive sight: all the planets of our solar system on display. The phenomenon — also known as a "planet ...

NASA launched the Pioneer 11 mission into the outer solar system. Pioneer 11 would become the first spacecraft to fly by ...