What processes are responsible for the intense volcanic activity on Jupiter’s innermost Galilean moon, Io, and what can this tell us about volcanic worlds that could exist throughout the cosmos? This is what a recent study published in Nature hopes to address as an international team of scientists led by the California Institute of Technology (Caltech) investigated how the tidal heating forces that Io experiences during its eccentric (oval-shaped) orbit around Jupiter. This study has the potential to help researchers better understand the tidal heating responsible for Io’s volcanic activity and what this can teach us about tidal heating on exoplanets.
For the study, the researchers gathered data on Io’s tidal heating activity from two flybys conducted by NASA’s Juno spacecraft, which is currently tasked with studying Jupiter and its Galilean moons. The team then combined this recent data with data from NASA’s long-retired Galileo spacecraft, which studied the Jupiter system in the 1990s. In the end, the researchers determined that Io has a mostly solid mantle that lacks a shallow magma ocean, indicating the immense tidal heating that Io experiences is not responsible for creating global magma oceans.
“Juno’s discovery that tidal forces do not always create global magma oceans does more than prompt us to rethink what we know about Io’s interior,” said Dr. Ryan Park, who is a Juno co-investigator and supervisor of the Solar System Dynamics Group at NASA JPL and lead author of the study. “It has implications for our understanding of other moons, such as Enceladus and Europa, and even exoplanets and super-Earths. Our new findings provide an opportunity to rethink what we know about planetary formation and evolution.”
What new discoveries about Io will researchers make in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
Sources: Nature, ScienceDaily, NASA
Image of Io’s north polar region obtained by NASA’s Juno spacecraft on Dec. 30, 2023, with this data being used to help scientists understand Io’s interior processes. (Credit: Image data: NASA/JPL-Caltech/SwRI/MSSS; Image processing by Gerald Eichstädt)