Photo credit: www.sciencenews.org

Insight into Io’s Volcanic Landscape: New Discoveries about Lava Lakes

Jupiter’s moon Io stands out as the most volcanically active entity in our solar system, featuring an astonishing array of erupting volcanoes. Recent findings have uncovered several dozen lava lakes, as detailed in the February edition of the Journal of Geophysical Research: Planets. These findings offer new perspectives on the dynamics of magma movement beneath Io’s surface.

The volcanic activity on Io has likely persisted for its entire 4.6 billion year history, first brought to light during the Voyager spacecraft flyby in 1979. The intense gravitational forces exerted by Jupiter and its neighboring moons create significant tidal stresses on Io, causing the moon to deform by substantial amounts. According to Alessandro Mura, a planetary scientist from Italy’s National Institute for Astrophysics in Rome, this deformation leads to significant heating of the moon’s interior.

Utilizing infrared imagery acquired through NASA’s Juno spacecraft—operational around Jupiter since 2016—Mura’s research team identified over 40 lava lakes, with diameters ranging from approximately 10 to 100 kilometers. This scale greatly surpasses that of terrestrial lava lakes, which generally measure in the tens or hundreds of meters.

Earth-based volcanologist Einat Lev from Columbia University’s Lamont-Doherty Earth Observatory points out that planetary volcanism exhibits extremes that are often far greater than what is observed on Earth. “Many of the volcanic flows on other celestial bodies are significantly larger,” she remarked.

Earlier explorations have noted the existence of lava lakes on Io, although these analyses lacked depth. Mura and his colleagues highlighted that most of the newly identified lava lakes demonstrate a temperature gradient, being hottest at their edges. This observation suggests that a crust of solidified lava predominantly caps these lakes.

Alfred McEwen, a planetary geologist at the University of Arizona, who was not involved in this study, further supports this view, explaining that the cold conditions on Io facilitate immediate crust formation upon lava exposure.

The molten lava visible at the peripheries of these lakes may be indicative of the lakes’ interaction with their geological structures. Mura believes that the lava lakes, which are situated within steep-walled caldera-like features, experience surface crust disruption as they fill or drain. The friction against the steep walls breaks apart the crust, unveiling fresh lava below.

Moreover, the research brings to light the mechanisms through which magma circulates beneath Io’s surface and supplies these lava lakes. Notably, none of the lakes analyzed displayed a distinct hot spot at their centers, which implies that magma does not solely rise from beneath a lake’s center.

The scientists aspire to determine whether multiple lava lakes share a common magma reservoir. If true, these lakes could exhibit synchronized changes in size. Such insights could provide valuable knowledge about the underlying geological processes that drive Io’s remarkable volcanic activity. “These observations may offer a glimpse into what lies beneath Io’s rocky exterior,” says Mura.

Source
www.sciencenews.org