MathLiveOrbital period
Gives the time an object takes to complete one full orbit around another body from the semi-major axis of the orbit and the standard gravitational parameter of the system. For a planet, moon, asteroid or exoplanet orbiting a much more massive body, μ is G times the mass of the central body. For a binary star, μ is G times the sum of both masses. It is used in celestial mechanics for planets, moons, asteroids, exoplanets and binary stars.
T = 2\pi\sqrt{\frac{a^3}{\mu}}What the symbols mean
| orbital period, the time for one complete orbit (seconds) | |
| semi-major axis of the orbit (metres) | |
| standard gravitational parameter of the orbiting system, G times the central body's mass or, for a binary, G times the total mass of both bodies (m^3 s^{-2}) | |
| pi, the ratio of a circle's circumference to its diameter |
About this formula
- FieldPhysics
- TopicCelestial mechanics
- LevelUniversity
- Also calledperiod of orbit, revolution period, orbital period formula, Kepler's third law, orbit period from semi-major axis, time for one orbit
- SourceWikidata Q37640
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