High-temperature hot spots on Io as seen by the Galileo solid state imaging (SSI) experiment

A. S. McEwen; D.P. Simonelli; D.R. Senske; K.P. Klaasen; L. Keszthelyi; T. V. Johnson; P.E. Geissler; M. H. Carr; M. J. S. Belton

doi:10.1029/97gl01956

USGS · 70019220

High-temperature hot spots on Io as seen by the Galileo solid state imaging (SSI) experiment

A. S. McEwen·D.P. Simonelli·D.R. Senske·K.P. Klaasen·L. Keszthelyi·T. V. Johnson·P.E. Geissler·M. H. Carr·M. J. S. Belton

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Abstract

High-temperature hot spots on Io have been imaged at ∼50 km spatial resolution by Galileo's CCD imaging system (SSI). Images were acquired during eclipses (Io in Jupiter's shadow) via the SSI clear filter (∼0.4–1.0 µm), detecting emissions from both small intense hot spots and diffuse extended glows associated with Io‧s atmosphere and plumes. A total of 13 hot spots have been detected over ∼70% of Io–s surface. Each hot spot falls precisely on a low-albedo feature corresponding to a caldera floor and/or lava flow. The hot-spot temperatures must exceed ∼700 K for detection by SSI. Observations at wavelengths longer than those available to SSI require that most of these hot spots actually have significantly higher temperatures (∼1000 K or higher) and cover small areas. The high-temperature hot spots probably mark the locations of active silicate volcanism, supporting suggestions that the eruption and near-surface movement of silicate magma drives the heat flow and volcanic activity of Io.

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A. S. McEwen, D.P. Simonelli, D.R. Senske, K.P. Klaasen, L. Keszthelyi, T. V. Johnson, P.E. Geissler, M. H. Carr, M. J. S. Belton. 1997-10-15. High-temperature hot spots on Io as seen by the Galileo solid state imaging (SSI) experiment. https://doi.org/10.1029/97gl01956

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