The astronauts will lose contact with Earth for about 40 minutes as they pass behind the Moon, which will block radio and laser signals from communication between the spacecraft and Earth. This experience was described by author Michael Cosby in his 1974 memoir, "Couche", as he felt "truly alone" but did not feel fear or loneliness. However, Cosby believes this situation could change as Nasa begins to build a Moon base and explore further the lunar surface.