The project comes after several prominent scientists and environmentalists urged humans to look beyond Earth to ensure the survival of the species.

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Physicist Stephen Hawking, a Cambridge University professor, has previously warned that the "long-term survival of the human race is at risk" if it is confined to a single planet.

He said: "Sooner or later, disasters such as an asteroid collision or a nuclear war could wipe us out. But once we spread out into space, and establish independent colonies, our future should be safe."

Professor James Lovelock, a British environmentalist who has worked with NASA designing scientific equipment to try to find life on other planets, has echoed Mr Hawking's concerns. In his book The Revenge of Gaia, he warns that climate change could almost wipe out humanity, causing the world's population to drop from 6.5 billion to as little as 500 million.