Rotation and Orbit

- Recall that the Moon’s rotational period and orbital period are both 27.3 days

The Earth rotates in less than 24 hours and travels around the Sun over 365 days.

The Moon orbits the Earth in 27 Earth days, 7 Hours, 43 minutes and 7 seconds (Approx. 27.3 days). A day on the Moon is also 27.3 of our days long. We see two full Moons 29 days apart as the Earth is also moving in space while the Moon orbits around it.

The orbit and rotation period of the Moon are identical.

The Moon has a synchronous (or captured) rotation which means it keeps the same side or face towards the body it orbits. This means that from Earth only one side or hemisphere can be seen.

The Moon has a day and night and receives sunlight on every area of its surface; an exception to this are deep craters at the poles which remain in permanent darkness.


Image taken from EPOXI spacecraft (NASA)

Links New Window

The Moon's Rotation Jim Loy site

Moon Rotation Movie Download a movie of the Moon rotating

Bad Astronomy Overview of the Moon's rotation

Pages in other sections

See the Phases page in the Interactions section for more information


  • What is the name given to the type of rotation of the Moon around the Earth?
  • Why can we only see one side of the Moon?
  • How long is a day on the Moon?