Jupiter_Day_20

Day 20 of One Track a Day / One Planet a Day. Ninth planet visited, continuing outward past Mars and the asteroid belt. Jupiter's four largest moons — Io, Europa, and Ganymede — are locked in the Laplace resonance: an exact 4:2:1 orbital ratio that's held stable for billions of years. This track builds that lock as a literal three-voice polyrhythm. A fourth moon, Callisto, joins as a looser texture voice deliberately left off the grid — its real ratio to Ganymede is ≈2.33:1, close to but not quite locked, so it drifts in and out of phase instead of clicking into place. Tempo is Jupiter's own signature: 99 BPM, tied to its real ~9h55m rotation — the fastest of any planet despite being the largest. Bb Minor. The Great Red Spot gets its own section, and its recession is real too — the storm has been visibly shrinking for decades. Approach → Resonance Lock → Great Red Spot → Recession → Onward. 99 BPM · Bb Minor · ~4:51 Ancient rhythms. Future landscapes. One continuous journey.