In an incredible breakthrough, a team of international astronomers have for the first time ever witnessed the birth of a planetary system beyond Earth's sun that could one day resemble our own. The ...

Astronomers believe they have uncovered evidence of a previously unknown ninth planet lurking in the not-too-distant reaches of the solar system. This hypothetical world, dubbed "Planet Y," could be ...

There's something big missing from our solar system — and that may be a good thing. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Planetary ...

Five years ago, astronomers revealed a spectacular collection of other worlds: the TRAPPIST-1 system. Newspapers around the world printed the discovery on their front pages: Astronomers had found that ...

Astronomers poring over four years of data from NASA’s Kepler spacecraft have discovered a star that’s 11.2 billion years old and has at least five Earth-size planets. “We thus show that Earth-size ...

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 ...

The newborn planetary system appears to be emerging 1,300 light-years away around a baby star known as HOPS-315. Planet-forming materials were first identified using NASA's James Webb Space Telescope.