This artist’s concept depicts one of the solar system’s inner planets slamming into Earth after being nudged on a collision course by a passing star. Such a world-shattering cataclysm is extremely ...

Astronomers are closing in on one of the most tantalizing possibilities in planetary science, evidence that a previously unknown world may be lurking in the outer reaches of the solar system. The ...

Jupiter is already the biggest planet by far in our solar system, but new research suggests it was somehow once even larger than it is now. Twice as large, in fact. To put that into context, those ...

These icy bodies orbit the sun just like the major planets, yet they follow their own rules, often traveling along elongated ...

There are a couple of ways that scientists can date planets, so which planets formed first in our solar system? When you purchase through links on our site, we may earn an affiliate commission. Here’s ...

Earth may have a moon today because a nearby neighbor once crashed into us, a new analysis of Apollo samples and terrestrial rocks reveals. When you purchase through links on our site, we may earn an ...

It was almost 100 years ago that Clyde W. Tombaugh discovered Pluto. That was the last planet found until 1992, when humans found another one. But this new planet wasn't in our solar system—it was ...