China advances plans for dual solar system boundary missions China has published coordinated papers outlining dual missions ...

Planet 9 sits at the edge of scientific imagination, promising either an epic expansion of the Solar System or a lesson in ...

Which way is ‘down’ has a different answer depending on where you are on Earth, in the solar system, in our galaxy and beyond ...

There have been questions about a mysterious ninth planet in our solar system for nearly a decade. Pluto was unseated as number nine in 2006. Now, a group of international researchers say they may ...

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 ...

Astronomers have discovered the earliest seeds of rocky planets forming in the gas around a baby sun-like star, providing a precious peek into the dawn of our own solar system. It’s an unprecedented ...

"It's very rare to discover an object both large and with an exotic orbit." When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. A potential new dwarf ...

The sun’s outer atmosphere resembles a pufferfish.

LONDON — The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper's authors have ...

Our Sun’s outer atmosphere, the corona, is millions of degrees hotter than it should be, and no one knows why.