Io’s dynamic surface and atmosphere

Jupiter’s volcanic moon Io hosts our most dramatic example of a surface environment that is continuously being created and modified by interior processes. Tidal heat dissipated in Io’s interior is advected to the surface by magma, which erupts at volcanic centers scattered across the body. Sulfurous and alkali species outgassed from the magma form Io’s atmosphere and coat its surface, and are ultimately either recycled back into the interior or lost to the jovian system where they source a system of energetic ionized and neutral material orbiting Jupiter. These processes occur over a range of timescales, from transient volcanic bursts and the nightly collapse of the bulk SO₂ atmosphere to seasonal changes and slowly-developing geological features. Temporal coverage of Io’s evolving reservoirs provides insight into its volcanism and broadly sheds light on the mechanisms of heat and material exchange between the interiors, surfaces, and atmospheres of geologically active moons. In the years since the Galileo mission, Earth-based observations, sensitive to a wide array of observable signatures, have continued to reveal the nature of Io’s volcanic and atmospheric processes. This talk will discuss recent work that has contributed to our current understanding of the Solar System’s most volcanically active world, and will highlight some fundamental areas where our understanding remains far from complete.