A critical part of a balanced exploration program, competed missions are scientist-led projects that cost less and occur more frequently than large, flagship-class missions.

A giant stellar explosion is going to be visible from Earth. Here's how to see it.

This week brings updates on the next missions to rove — and maybe even fly — over the surface of Mars.

They may not be real moons, but they're worth exploring and studying.

The Sun was in the spotlight this week, with a huge solar storm and the biggest solar flare in over a decade.

An overview of one of international space law’s foundational documents.