Mean-Motion Resonance · Laplace 1:2:4
unseel.com · Io · Europa · Ganymede · integer period lock
Period ratio 1 : 2 : 4
Laplace angle φ ≈ 180°
State
Io · P = 1.77 d
Europa · P = 3.55 d
Ganymede · P = 7.15 d
Conjunction / resonant angle
Unseel.com · Mean-Motion Resonance