The universe has quasi-moons, mini-moons, and moonlets, but no official definition of what counts as a moon.

In a startling new observation, the James Webb Space Telescope (JWST) has detected a planet with an atmosphere made almost ...

Arizona stargazers, mark your calendars because on Friday, Sept. 19, the night sky will host a celestial conjunction. Not to be confused with an alignment, a conjunction occurs when two or more ...

It's been a year full of celestial events, which may have sparked an interest in astronomy for many. When looking up at the night sky, it's easy to get confused about what you're looking at, ...

Wondering if it's a full moon tonight or if the planet Venus and Regulus star will be visible again today? Here's what to know about this weekend's celestial events. Tonight's waning crescent moon ...

Mike Brown is convinced that beyond Neptune, at the far reaches of our solar system, there's an unseen giant planet. "This is the 5th largest planet in our solar system, lurking out there, waiting to ...

It's an evocative idea that has long bedeviled scientists: a huge and mysterious planet is lurking in the darkness at the edge of our solar system, evading all our efforts to spot it. Some astronomers ...

The newly discovered world is called GJ 251c and it is a super-Earth orbiting a red dwarf star less than 20 light-years away.

A visible line of planets has for weeks been the talk of astronomers and hobbyist stargazers who have sought to catch a sight of our solar system's worlds. Online chatter and a frenzy of media ...

Saturn is the planet of discipline, boundaries and structure — its influence will challenge you to grow. Here's everything ...

A celestial conjunction featuring the moon, Venus, and the star Regulus will be visible on Friday, Sept. 19. This event will be bright enough to be seen without a telescope, though clouds could ...