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Orbit Sandbox

Change an orbit's shape and watch its speed change. See Kepler's second and third laws in action.

ESO/S. Guisard (www.eso.org/~sguisard) (CC BY 4.0)

Orbit Sandbox

Period

Speed now

Fastest (periapsis)

Slowest (apoapsis)

Closest distance

Farthest distance

Kepler's 3rd law check: T² / a³

Try a real orbit Central body Semi-major axis: Eccentricity: Inclination: Argument of periapsis: Longitude of ascending node:

Show equal areas (Kepler's 2nd law) Side view

The animation plays every orbit in 8 seconds; the period shown is the real one.

Data table (text alternative)

Distance and speed at twelve equal time steps around the orbit
Time step	Distance from the Sun now	Speed now

Tools and lessons use simplified models for learning only. They must not be used for navigation, mission planning or any operational decision. Certificates are free and non-accredited. Read the educational content disclaimer