Juno's Jovian Infrared Auroral Mapper (JIRAM) instrument, originally intended to study Jupiter's atmosphere, was able to capture detailed infrared images of Io during close flybys in 2023. These images revealed extensive lava lakes dotting Io's surface.
The data suggests that these lakes are constantly in flux, with a central region of cooler, solidified lava surrounded by a ring of much hotter, molten material. This hotter ring is thought to be where new lava from Io's interior erupts onto the surface. Scientists believe this process is driven by the tidal forces exerted by Jupiter and other nearby moons, which constantly stretch and squeeze Io.
These findings not only provide a clearer picture of Io's volcanic activity but also offer insights into the moon's internal composition. The presence of ongoing eruptions suggests a large reservoir of molten rock beneath the surface.
Io's volcanoes are unlike anything found on Earth. Earth's volcanoes erupt with molten rock, or magma, that cools and solidifies into new rock. On Io, the intense tidal heating keeps the lava lakes molten, creating a fiery landscape unlike any other in our solar system.