It’s not a large moon compared to some of its neighbors, but Jupiter’s moon Io is extremely active, with hundreds of volcanoes spewing out lava plumes. tens of miles Above its surface, according to NASA. Infrared technology aboard the space agency’s Juno probe mapped two such eruptions in February, returning valuable data about mysterious events beneath Io’s surface. Researchers shared their insights on the matter in paper Published last week.
From a distance of about 2,400 miles, the probe’s JIRAM (Jovian Infrared Auroral Mapper) instrument revealed “that Io’s entire surface is covered with lava lakes in caldera-like features,” explained Alessandro Mura, a Juno co-investigator at the National Institute of Astrophysics in Rome. On Earth, a caldera is a crater formed by the collapse of a volcano. Io is about a quarter the size of Earth in diameter, and slightly larger than Earth’s moon.
“In the area of Io’s surface where we have the most complete data, we estimate that about 3% of it is covered by some kind of molten lava lake,” Mora said. Juno’s JIRAM instrument came via the Italian space agency Agenzia Spaziale Italiana.
According to Mora, lead author of the Io paper, the probe’s flyby reveals the most common type of volcanism on Jupiter’s hottest moon — “enormous lakes of lava where magma rises up and down.”
“The lava crust is forced to break up against the walls of the lake, forming the typical lava ring seen in Hawaiian lava lakes,” he added. “The walls are likely hundreds of meters high, which explains why the magma spill is generally not noticed.”
Researchers are still studying data collected by the two Juno missions around Io, which occurred in February 2024 and December 2023.
