How often does the moon return to the same place in sky?  
I understand that it has a monthly new/ full cycle. But how often does the moon return to the same place in the sky?
How often does the moon return to the same place in sky?
I understand that it has a monthly new/ full cycle. But how often does the moon return to the same place in the sky?
Asked by: djonas
Category: Natural World

Asked on: 1st Feb. 2011
Ending on: 15th Apr. 2011

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  2   :: Suggestion by klimber on 24th August 2010

The complete lunar cycle (New Moon to New Moon) is called a "Lunation" and takes 29.5 days. This is the time between the moon being in the exact same phase - so for example full moon to full moon.

However, this takes into account the fact that the earth is moving around the sun, so the moon isn't actually in the same location in the sky.

It's in the same "location" (relative to an earth observer) about 2 days earlier than that (27.5 days), that's why the moon appears to "move" East if you observe at the same time on consecutive nights.

So, I think that ~27.5 days is what you're looking for..

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