A Hellacious Two Weeks on Jupiter’s Moon Io

Three massive volcanic eruptions occurred on Jupiter’s moon Io within a two-week period in August of last year. This led astronomers to speculate that such “outbursts,” which can send material hundreds of miles above the surface, might be much more common than they thought.

These images show Jupiter's moon Io obtained at different infrared wavelengths (in microns, μm, or millionths of a meter) with the W. M. Keck Observatory's 10-meter Keck II telescope on Aug. 15, 2013 (a-c), and the Gemini North telescope on Aug. 29, 2013 (d). The bar on the right of each image indicates the intensity of the infrared emission. Image courtesy of Imke de Pater and Katherine de Kleer.

These images show Jupiter’s moon Io obtained at different infrared wavelengths (in microns, μm, or millionths of a meter) with the W. M. Keck Observatory’s 10-meter Keck II telescope on Aug. 15, 2013 (a-c), and the Gemini North telescope on Aug. 29, 2013 (d). The bar on the right of each image indicates the intensity of the infrared emission. Image courtesy of Imke de Pater and Katherine de Kleer.

“We typically expect one huge outburst every one or two years, and they’re usually not this bright,” said Imke de Pater, professor and chair of astronomy at the University of California, Berkeley, and lead author of one of two papers describing the eruptions. “Here we had three extremely bright outbursts, which suggest that if we looked more frequently we might see many more of them on Io.”

De Pater’s long-time colleague and coauthor Ashley Davies, a volcanologist with NASA’s Jet Propulsion Laboratory in Pasadena, California, said that the recent eruptions match past events that spewed tens of cubic miles of lava over hundreds of square miles in a short period of time.

“These new events are in a relatively rare class of eruptions on Io because of their size and astonishingly high thermal emission,” Davies said. “The amount of energy being emitted by these eruptions implies lava fountains gushing out of fissures at a very large volume per second, forming lava flows that quickly spread over the surface of Io.”

Jupiter's moon Io saw three massive volcanic eruptions within a two-week period last August. This Aug. 29, 2013, outburst on Io was among the largest ever observed on the most volcanically active body in the solar system. Image Credit: Katherine de Kleer/UC Berkeley/Gemini Observatory.

Jupiter’s moon Io saw three massive volcanic eruptions within a two-week period last August. This Aug. 29, 2013, outburst on Io was among the largest ever observed on the most volcanically active body in the solar system. Image Credit: Katherine de Kleer/UC Berkeley/Gemini Observatory.

More information