# # Program information file # PROGRAM_ID 2024A028 PROGRAM_TITLE Short, frequent observations of Io to support the Juno mission: understanding volcanism, constraining Loki, and linking outbursts to plasma torus enhancements PROGRAM_INV1 Madeline Pettine PROGRAM_INV2 Julie Rathbun PROGRAM_INV3 PROGRAM_INV4 PROGRAM_INV5 PROGRAM_SCICAT major planets / satellites PROGRAM_ABSTRACT_BEG We propose observing Io, the innermost moon of Jupiter, in the K-, L-, and M-bands every few weeks. Our short observations include 20-minute sunlit service observations that will view all longitudes of Io and provide brightness and location information on the bright volcanoes on Io, including outbursts, which are of particular interest to the science of Io's volcanoes. We will also perform 90-minute occultation observations that will give higher-resolution 1-dimensional mapping of volcanoes as they pass behind the limb of Jupiter, but can only view the sub-Jovian hemisphere [including Loki, a bright, periodic volcano of particular interest]. The goals of this project are to map long-term volcanic flux in order to study tidal heating, time the period and duration of Loki's brightening to better understand its physics, and to support studies of the plasma torus [which is fed by Io's volcanism]. This semester's observations are particularly crucial for supporting Juno's extended mission, as it has two close fly-bys [including a historically close fly-by of 2000 km, closer than any instrument since 2001] that coincide closely with ground-observable occultations. The IRTF has conducted high-cadence ground-based observations of Io for decades which have been critical in revealing trends in Io's volcanic behavior, but recent studies [Tate et al. 2023b, in review] have suggested that Io's outbursts changed in location and frequency over the last decade. To understand why these global trends changed, how often they change, and the extent to which they changed, we must understand both the vault of historical data the IRTF has provided while continuing to observe Io. PROGRAM_ABSTRACT_END