So very cold: Astronomers find lonely planet without a sun

An artist's conception of PSO J318.5-22. (MPIA/V. Ch. Quetz)

A team of astronomers working at the University of Hawaii at Mamoa has discovered a new planet, one without a sun.

"We have never before seen an object free-floating in space that looks like this. It has all the characteristics of young planets found around other stars, but it is drifting out there all alone. I had often wondered if such solitary objects exist, and now we know they do," team leader Michael Liu said in a statement.

The free-floating planet, known as "PSO J318.5-22," is roughly 80 light-years away from Earth, according to the astronomers. It is also believed to be relatively young — around 12 million years old. Earth, on the other hand, is believed to be around 4.5 billion years old. Astronomers have compared PSO J318.5-22 to a young Jupiter.

Ever since the mid-1990s, scientists have found hundreds of “exoplanets” using techniques that involve "detecting the decreased transmission of light as a planet passes in front of its sun," the U.K.'s Independent explains.

PSO J318.5-22 was found in an altogether different way. Astronomers were apparently searching for brown dwarfs (failed stars), which are faint and red in color, via the Pan-STARRS 1 telescope. It was then that the team came upon the planet.

Niall Deacon, who served as co-author on the study, said in the news release that "planets found by direct imaging are incredibly hard to study, since they are right next to their much brighter host stars."

Because PSO J318.5-22 isn't orbiting a star, it's going to make it easier to examine and easier for experts to study.