Volcanic Origin of Disulfur Monoxide (S2O) on Io

Mikhail Yu Zolotov, Bruce Fegley

Research output: Contribution to journalArticle

24 Scopus citations


We use chemical equilibrium calculations to model S2O formation by high temperature thermochemical reactions in volcanic gases on Io. The calculations predict formation of 1-6% S2O gas at observed hot spot temperatures in SO2-S2gas mixtures at pressures of 1-100 bars in volcanoes on Io. The S2O abundance increases with increasing pressure (up to ~6% at 100 bars) and is relatively insensitive to temperature and the bulk O/S ratio over wide ranges. Condensation of volcanic S2O provides a plausible explanation for the solid S2O that has been suggested to be present on Io's surface (e.g., around the Pele volcano).

Original languageEnglish (US)
Pages (from-to)293-297
Number of pages5
Issue number2
StatePublished - Jun 1 1998
Externally publishedYes


ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

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