NASA says Io doesn't have an ocean of lava, shocking scientists

On December 15, 2024, NASA's Juno spacecraft provided new insights regarding Jupiter's innermost moon, Io. This groundbreaking research indicated that Io, long thought to have a shallow sea of magma beneath its surface, likely does not possess a subsurface magma ocean as previously assumed. The study, published in Nature, utilized data collected from Juno, which has been orbiting the gas giant Jupiter since 2016, and marked the closest any spacecraft has come to Io in 20 years since the Galileo mission. One of the key factors in this conclusion was an evaluation of Io’s tidal heating caused by its gravitational interactions with Jupiter and its neighboring moons. Scientists had hoped that the new images and experiments conducted during the Juno flyby would clarify whether magma exists in patches or as a more globally distributed ocean beneath the surface. However, the results suggested that the tidal energy generated by these gravitational interactions is insufficient to melt the moon’s interior, and therefore, a magma ocean was deemed unlikely. This research challenges previously held notions in the scientific community, particularly among experts studying exoplanets, that strong tidal heating would inherently lead to the formation of magma oceans. The unique geological activities on Io, characterized by its intense volcanic eruptions, could draw from other sources, shifting the focus of investigation towards other mechanisms of volcanic activity. Scientists highlighted that the findings might reshape the understanding of tidal heating not only on Io but across other moons in the solar system. Overall, the conclusions reached from Juno's observations provide a significant paradigm shift in how celestial bodies with intricate gravitational dynamics can behave. As the study details, Io offers a valuable case study that informs our understanding of planetary geology and potential volcanic activity in the broader context of the universe. The research underscores the importance of continuous exploration and the need to revise preconceived ideas based on new data and findings.