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Astronomy & Space vocabulary · Orbits & Gravity

Orbital period

Meaning in astronomy & space, with examples

nounCommon term

In astronomy & space, orbital period means: The time an object takes to complete one full orbit around another object. Earth's orbital period around the Sun is about 365.25 days.

In Turkish: yörünge periyodu, dolanma süresi

How it is used

Used for planets, moons, satellites and exoplanets. Astronomers work out an exoplanet's orbital period from regular dips in its star's light. Satellite operators give orbital periods in minutes.

Example sentences

  1. Mars has an orbital period of about 687 Earth days.

  2. Satellites in low orbit have an orbital period of around 90 minutes.

Common collocations

  • an orbital period of
  • short orbital period
  • calculate the orbital period
  • orbitThe curved path that an object such as a planet, moon or satellite follows around another object because of gravity. As a verb, it means to move along this path.
  • Kepler's lawsThree rules published by Johannes Kepler in the early 1600s: planets move in ellipses, they move faster when closer to the Sun, and orbit size is linked to orbital period.
  • transitThe passage of a planet or moon across the face of a larger body, such as Mercury crossing the Sun's disc or an exoplanet passing in front of its star.
  • low Earth orbitAn orbit relatively close to Earth, usually below about 2,000 km. The space station and most Earth observation satellites fly in low Earth orbit.

More terms: Orbits & Gravity

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