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When astronomer Simon Marius discovered that Jupiter had 4 moons, (he did so about a month before Galileo) he took his friend Johannes Kepler’s advice and gave them rather cheeky names. If you’re not up on your Roman mythology Jupiter was basically God of gods. His marriage to Juno was a rocky one, mainly because Jupiter took his share of lovers. Kepler’s suggestion: name the moons after Jupiter’s main lovers. That’s Io, Callisto, Ganymede and Europa. And it was a pretty good joke as it was, for four centuries. But when NASA sent a probe to check up on Jupiter and his lovers in 2011, it was named after his wife Juno: the planetary punchline we didn’t know we needed.
You’ve been listening to Mozart’s Symphony No. 41 in C major, also known as the Jupiter symphony. It’s the last symphony that he composed and it’s on the short list of the greatest in the history of classical music.