Record Volcanic Event on Io

NASA's Juno spacecraft has observed the most energetic volcanic event recorded in the solar system on Jupiter's moon Io. The synchronized eruptions covered an area of 40,400 square miles (65,000 square kilometers), suggesting an interconnected network of magma reservoirs beneath Io's surface.

Unprecedented Energy and Scale

The eruptions released an estimated 140 to 260 terawatts of energy, surpassing the previous record of 80 terawatts from Io's Surt volcano in 2001.

For comparison, the 1980 Mount St. Helens eruption had a power of 52 terawatts. Alessandro Mura of the Italian National Institute for Astrophysics (INAF) stated that the event involved multiple active sources that brightened simultaneously by over a thousand times compared to typical levels. This synchronicity indicates a single, vast eruptive event that propagated hundreds of kilometers underground.

Observation Details

The volcanic activity occurred on December 27, 2024, during a close Juno fly-by at 46,200 miles (74,400 kilometers) above Io's surface. Io, with a diameter of 2,263 miles (3,643 km), hosts approximately 400 active volcanoes. These are driven by gravitational tidal forces from Jupiter, which heat and melt Io's interior.

Implications for Io's Subsurface

The simultaneous eruption of multiple volcanoes suggests they are linked by extensive magma pools.

Mura's research team proposes that Io's subsurface and mantle may be porous and filled with magma, resembling a sponge.

The observation that not all known volcanoes in the region erupted implies the existence of distinct, unconnected magma networks.

Detection and Future Missions

Juno's Jovian InfraRed Auroral Mapper (JIRAM) instrument detected the outburst. While primarily designed for Jupiter's atmosphere and aurorae, JIRAM's infrared capabilities are also effective for identifying volcanic hotspots on Io. As part of its extended mission, Juno is conducting close encounters with Jupiter's Galilean moons. Upcoming fly-bys of Io will survey the moon's surface for new lava flows and ash deposits resulting from this significant volcanic eruption.