The Absorbent Pitch-Black Atmosphere of Hot Jupiter WASP-104b
Deep within the constellation Leo, circling a G-type star roughly 466 light-years from our solar system, lies one of the most physically extreme objects ever recorded by transit photometry . WASP-104b is a gas giant that defies conventional expectations of planetary reflection. While most gas giants possess an albedo —a measure of how much light they reflect—that ranges from 10% to 50%, this massive body occupies the extreme end of the scale, absorbing nearly all light that strikes its outer boundary. As a hot Jupiter , WASP-104b is locked in a tight, perilous orbit, circling its parent star once every 1.76 days. This proximity results in extreme tidal locking , ensuring that one side of the giant is forever scorched by its host star while the other perpetually faces the dark void of the cosmos. The chemical composition of the atmosphere is dominated by hydrogen and helium, yet it is the trace elements—likely atomic sodium and potassium—that give the gas giant its defining physical ch...