Apparently, When Ultramafic Rock Melts, Its Conductivity Spikes, And That's Why Io Distorts Jupiter...

Apparently, When Ultramafic Rock Melts, Its Conductivity Spikes, And That’s Why Io Distorts Jupiter’s Magnetic Field As Dramatically As It Does

“Later experiments in mineral physics found out that when ultramafic rocks, which are rocks very high in magnesium and iron — when those are melted, their conductivity shoots up by orders or magnitude. And it is that very high conductivity that can create the type of signature we have seen. So, we needed mineral physics to catch up with our data.”
 — For a long time, scientists have wondered why the magnetometer readings around the Jovean moon Io were so crazy. Turns out it’s because Io is so ultramafic. Io is also the most volcanic world in the entire solar system, due to a seething, 30-mile-thick ocean of magma just beneath its crust. Cool! (And very hot, with temperatures exceeding 1,200 degrees Celsius.)