New Research Challenges Existence of Global Magma Ocean

In a groundbreaking development, scientists now believe that Jupiter’s moon Io, the most volcanically active world in the solar system, may not possess a global magma ocean beneath its crust as once thought. This revelation challenges decades of assumptions about Io’s fiery interior and offers fresh insights into its volcanic activity.

A Shift in Understanding

The idea of a global magma ocean originated from data collected by NASA’s Galileo spacecraft in the late 1990s. Magnetic field readings suggested a highly conductive layer beneath Io’s crust, which was interpreted as a planet-wide molten rock reservoir. However, recent research led by scientists Yoshinori Miyazaki and David J. Stevenson from Caltech proposes a new model: Io’s subsurface may instead consist of a “magmatic sponge” — a partially molten layer composed of interconnected solid and liquid components.

Their findings, published in 2022, argue that sustaining a global magma ocean would require more heat than Io’s tidal forces are likely to generate. Instead, localized magma pockets, formed through intense tidal heating caused by gravitational interactions with Jupiter and neighboring moons, could explain the observed volcanic activity.