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 ...

Planetary size was determined pre-spacecraft by measuring the planet's angular diameter and its distance from Earth (in AU, later converted to terrestrial units after the AU was accurately measured ...

Using publicly available data from NASA’s Kepler space telescope, astronomers at the Harvard-Smithsonian Center for Astrophysics (CfA) estimate that six percent of red dwarf stars in the galaxy have ...

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 ...

Want life? Don't get too close to a gas giant planet. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Like huge playground bullies, planets like ...