Provided they host thick, hydrogen-dominated atmospheres, moons orbiting free-floating exoplanets could retain much of the heat generated deep within their interiors by tidal forces. Led by David Dahlbüdding at the Max Planck Institute for Extraterrestrial Physics and Giulia Roccetti at the Europea n Space Agency, a new study predicts that hydrogen could act as a potent greenhouse gas—potentially providing habitable conditions for billions of years after their host planets are first ejected from their stellar systems. The work has been published in Monthly Notices of the Royal Astronomical Society. ...read more read less