How long is a day on the moon?
If
you were standing on the Moon, you would always see the Earth in
exactly the same position, while the stars and the Sun moved around in
the sky. The Moon takes 27.3 days to complete an orbit around the Earth.
And this the same amount of time that it takes to turn once on its
axis.
Source : http://www.universetoday.com/20524/how-long-is-a-day-on-the-moon/