NASA announced the discovery of a planet 316 million miles from Earth that orbits every 12.8 days and is possibly even habitable. Gliese 12 b is a "super Earth exoplanet" that is nearly the same size as Earth or slightly smaller, according to a NASA news release. Exoplanets are planets outside of our solar system, NASA's website says.

We sometimes throw around terms like "Earth-like" and "potentially habitable" when talking about exoplanets, but a newly discovered world just 40 light-years away earns the distinction. Two international teams of astronomers report that Gliese 12 b is about the size of Venus,