Scientists using NASA’s Hubble Space Telescope have found evidence that a planet orbiting a distant star that may have lost its atmosphere but gained a second one through volcanic activity.

The planet, GJ 1132 b, is hypothesized to have begun as a gaseous world with a thick hydrogen blanket of atmosphere. Starting out at several times the diameter of Earth, this so-called “sub-Neptune” is believed to have quickly lost its primordial hydrogen and helium atmosphere due to the intense radiation of the hot, young star it orbits. In a short period of time, such a planet would be stripped down to a bare core about the size of Earth. That’s when things got interesting.


NASA/JPL-Caltech/Robert Hurt