Io and Jupiter

Phil Plaitt wants to teach you something about Jupiter and Io.

Jupiter’s magnetic field is enormous, which is fitting for the King of the Planets. It is far stronger and larger than Earth’s, and, not surprisingly, far more complex. Still, some parts of it are just like home: Jupiter has aurorae.

This has been known for years; the interaction of Jupiter’s magnetic field with its atmosphere creates the northern and southern lights in much the same way that it happens on Earth. But Jupiter has something we don’t: a volcanically active moon.

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