The images, to be published in Geophysical Research Letters, show surface features as small as 50 miles across, comparable to spacecraft imagery. The SHARK-VIS instrument helped identify a major resurfacing event around the volcano Pele. "Io, therefore, presents a unique opportunity to learn about the mighty eruptions that helped shape the surfaces of the Earth and the moon in their distant pasts," said Conrad, associate staff scientist at the Large Binocular Telescope Observatory.

The LBT is part of Mount Graham International Observatory, a division of the University of Arizona Steward Observatory. Studies like this one aim to understand why some solar system bodies are volcanic. These findings may also inform the study of volcanic worlds around nearby stars.

Io, slightly larger than Earth's moon, is the innermost of Jupiter's Galilean moons. It experiences constant gravitational forces from Jupiter, Europa, and Ganymede, resulting in frictional heat and continuous volcanic activity. The new images, taken on January 10, 2024, highlight volcanic features with a resolution not previously possible from Earth.

Monitoring Io's eruptions provides insights into its internal structure and the tidal heating mechanism driving its volcanism. Io's volcanic activity was first observed in 1979 by Linda Morabito during NASA's Voyager mission. Since then, various space and Earth-based observations have documented Io's dynamic nature.

Ashley Davies, a principal scientist at NASA's Jet Propulsion Laboratory, noted that the SHARK-VIS image revealed a resurfacing event involving the volcanoes Pele and Pillan Patera. "We interpret the changes as dark lava deposits and white sulfur dioxide deposits originating from an eruption at Pillan Patera, which partially cover Pele's red, sulfur-rich plume deposit," Davies said.

Co-author Imke de Pater, professor emerita of astronomy at the University of California - Berkeley, emphasized the importance of visible wavelength images provided by SHARK-VIS for identifying eruption locations and surface changes. These observations complement infrared data from spacecraft like Juno, currently orbiting Jupiter.

SHARK-VIS, built by the Italian National Institute for Astrophysics, was installed on the LBT in 2023. It includes a fast, ultra-low-noise camera that captures high-quality images by correcting atmospheric distortions. Gianluca Li Causi, data processing manager for SHARK-VIS, explained the data processing methods used to enhance image clarity.

SHARK-VIS instrument scientist Simone Antoniucci highlighted the instrument's potential for observing various solar system bodies, including asteroids. "The keen vision of SHARK-VIS is particularly suited to observing the surfaces of many solar system bodies, not only the moons of giant planets but also asteroids," he said. "We have already observed some of those, with the data currently being analyzed, and are planning to observe more."

Research Report:Observation of Io's Resurfacing via Plume Deposition Using Ground-based Adaptive Optics at Visible Wavelengths with LBT SHARK-VIS

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