For the first time, scientists have found evidence for a secondary atmosphere on an exoplanet, created by volcanism beneath the surface. The planet, GJ 1132 b, is thought to have once been a sub-Neptune, but now is a rocky world the size of Earth.
Artist’s concept of exoplanet GJ 1132 b. For the first time, scientists using the Hubble Space Telescope have found evidence of volcanic activity reforming the atmosphere on this rocky planet, which has a similar density, size, and age to that of Earth. New observations from Hubble have shown evidence of a second atmosphere that has replaced the planet’s first primordial atmosphere. Image via NASA/ ESA/ R. Hurt (IPAC/ Caltech).
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