Wired gets all hot about some of our solar system’s OTHER moons – specifically, the strange magnetism of the magma oceans of Io:
The magma sea is buried deep beneath the surface and is 20 to 30 miles thick, meaning it makes up at least 10 percent of the moon’s mantle by volume. The blisteringly hot reservoir, which feeds the moon’s many active volcanoes, would probably exceed temperatures of 1,200 degrees Celsius.
So how did the team only just figure this out, when its Io-hunting spacecraft Galileo threw itself into the burning atmosphere of Jupiter way back in 2003?
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“It turns out Io was continually giving off a ‘sounding signal’ in Jupiter’s rotating magnetic field that matched what would be expected from molten or partially molten rocks deep beneath the surface,” said Khurana.