A permanent human occupation of a site on the Moon. This is not the current stated goal of any nation, although US president George Bush made a long-range commitment on 20 July 1989 that the USA would go ‘back to the Moon, back to the future, and this time back to stay’. NASA acknowledged that planning a future lunar base would be helped by data gathered by its Lunar Prospector mission to map the lunar surface and search for ice deposits. Some private organizations, such as the international Artemis project and the Apollo Society of Honolulu, Hawaii, have the stated goal of establishing a private base on the Moon. A lunar base is one of the proposed milestones in the Aurora programme to put humans on Mars.