The Planet That Shouldn’t Be There

LHS 1903 is a small red M dwarf star orbited by a rocky planet and two gaseous planets. In a recent study, scientists used the European Space Agency’s CHEOPS satellite to investigate a fourth planet in this system and discovered that it might be rocky, like Venus. This is surprising because a planet order of rocky-gaseous-gaseous-rocky in a planetary system is rarely observed in the universe. Credit: ESA, CC BY-SA 3.0 IGO