Dark Side of the Moon Tour – A Piece for Assorted Lunatics", the name under which it made its press debut in February 1972 at London's Rainbow Theatre. The title changed for the first part of the US tour to "Eclipse (A Piece for Assorted Lunatics)" during April and May before reverting to "Dark Side of the Moon – A Piece for Assorted Lunatics" in September for the second part of the US tour and finally released in 1973 under the title of "The Dark Side of the Moon". Remarkably, at its first full live performance at Guildhall, Portsmouth, England on 21 January 1972, most of
Orbit of the Moon Orbit of the Moon The Moon orbits Earth in the prograde direction and completes one revolution relative to the stars in about 27.32 days (a sidereal month) and one revolution relative to the Sun in about 29.53 days (a synodic month). Earth and the Moon orbit about their barycenter (common center of mass), which lies about from Earth's center (about of the radius of Earth). On average, the distance to the Moon is about from Earth's center, which corresponds to about 60 Earth radii. With a mean orbital velocity of 1.022 km/s (0.635 miles/s), the Moon covers a distance approximately