Space. It's really, really big. How big is it? Well, according to astronomers, the observable universe is around 92 billion light-years in diameter, but that's all we can see (hence the word ...

For centuries our solar system was the only planetary system known to humans. We had no proof other worlds existed beyond those in our own cosmic backyard, and we imagined that if other planetary ...

Is our Milky Way galaxy home to other planets the size of Earth? Are Earth-sized planets common or rare? NASA scientists seeking answers to those questions recently revealed their discovery. “We went ...

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 ...

When two giant planets collide, an even bigger world may be born. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Based on new simulations, ...

Our solar system may be the odd one out. Across the Milky Way, astronomers keep finding super-Earths, planets larger than our ...