Buzz Aldrin, the second man on the Moon, has issued a stark warning that America must invest now in the space agency Nasa, or surrender leadership of space exploration to Russia and China. In an interview with The Sunday Telegraph, Mr Aldrin revealed that he intends to lobby Barack Obama and John McCain, the two US presidential candidates, in an effort to ensure they find sufficient funds for Nasa's goal to establish a permanent base on the Moon and then send a manned mission to Mars.