Heliocentric Orrery

—

—Paused

Scale & method

Time: True sidereal periods — Neptune’s year is 164.8 Earth years
Size: r′ = 4 · log₁₀(1 + D / 10,000 km)
Planets: d′ = R☉′ + 110 · log₁₀(1 + s / 50M km)
Moons: d′ = Rₚ′ + 7 · log₁₀(1 + s / 100,000 km)

D = diameter, s = gap from the parent’s surface, ′ = scene units (u). Orbits are drawn circular and coplanar, placed by real mean longitude. Rings keep true proportion to their planet. Axial spin is exact up to 3 turns per second on screen, then held there so it stays readable.

—

Drag to orbit · scroll to zoom · right-drag to pan
Click a body · Space pauses · 0–8 jump

The orrery couldn’t start

—