A recent study found that Jupiter was once twice the size that it is now, making it big enough to swallow up 2,000 Earths.

Jupiter, roughly 562 million miles from Earth today, has nearly 100 moons. But Batygin and his collaborator Fred Adams' ...

This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights. The size of the solar system is defined by the ...

The six found so far are roughly two to three times the size of Earth, but with densities closer to the gas giants in our own solar system. Pitts said most of the planets are smaller than Neptune.

Scientists have identified an object about 435 miles (700 km) wide inhabiting the frigid outer reaches of our solar system that might qualify as a dwarf planet, spotting it as it travels on a highly ...

Gareth Dorrian does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond ...