Physics • Education

Orbital Mechanics

Interactive Kepler orbital mechanics simulator. Explore elliptical orbits, eccentricity, and the laws of planetary motion with real-time physics.

Simulation

Yellow/orange glowing body = central star. Colored bodies = orbiting planets. The dotted line shows the orbital path, foci mark the orbit geometry, and the blue arrow shows velocity direction.

Controls

Simulation Mode

Eccentricity (e): 0.5

Semi-Major Axis (km): 150

Central Mass (M☉): 1.0

Speed Multiplier: 1.0x

Display Options

Presets

Orbital Parameters

Semi-Major Axis (a)

150 km

Eccentricity (e)

0.50

Orbital Period (T)

1.00 year

Current Velocity

29.8 km/s

Distance from Focus

100 km

Specific Orbital Energy

-0.50 km²/s²

Periapsis (r_p)

75 km

Apoapsis (r_a)

225 km

All values update in real-time. Vis-viva equation: v² = GM(2/r − 1/a). Period: T² = 4π²a³/GM (Kepler's Third Law).