Identification of gaseous SO2 and new upper limits for other gases on Io

Abstract

Gaseous SO2 has been identified on Io. The estimated abundance of 0.2 cm atm is consistent with an atmosphere in equilibrium with solid SO 2 at the local surface equilibrium temperature. Preliminary upper limits for several gases, including sulphur compounds and other terrestrial volcanic emissions have been derived. Io is apparently depleted in hydrogen, carbon and nitrogen. © 1979 Nature Publishing Group.