What determines the speed of an object orbiting our planet? © iStock

What determines the speed of an object orbiting our planet?

The speed of an object's orbit around earth depends on the object's axis - find out how here.

Asked by: Hafiz Malghani, Pakistan

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Objects captured by the Earth’s gravitation typically have elliptical orbits. The mean orbital speed of the object depends only on the Earth’s mass and the semi-major axis (half the longest diameter) of the object’s orbit. However, the orbital speed changes depending on where in the orbit the object is. It will 
be greatest when closest to Earth and least when furthest from Earth.


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