Comparable to shaving foam, astronomers find the wispiest planets yet. They're in the southern "flying fish" constellation.

NASA's Transiting Exoplanet Survey Satellite or TESS has found what NASA calls the two "puffiest" worlds ever found. While they're as big as our gas giants, they're so light and airy that their density is apparently comparable to cotton candy.

NASA’s TESS mission discovered two unusually puffy planets, one larger than Jupiter and one about the same size, but both are as light as cotton candy.

A pair of distant worlds is forcing astronomers to rethink what it means to be a planet. New observations reveal two gas giants so light and inflated they resemble cosmic clouds more than solid worlds.