Three of the 12 American astronauts who flew to the Moon in the space programs that began 30 years ago have called for a commitment to a mannedmission to Mars. The astronauts - Neil Armstrong, Buzz Aldrin and Gene Cernan - made their appeal during a news conference at the Kennedy Space Centre in Florida to commemorate the 30th anniversary of the launch of Apollo 11, which took the first men to the Moon.
Neil Armstrong, who made the first historic Moon-walk, said the Apollo missions had demonstrated that "humanity was not forever chained to this planet", and that opportunity was unlimited.
He and his fellow Apollo 11 astronaut, Edwin "Buzz" Aldrin, said they would like to see man reach Mars within 20 years.
"To put together the effort that it takes to get there once, twice, three times, and then turn our backs on it would be very sad for me and I would not like to see that happen," said Aldrin.
"We could do it in 2020 if we committed to it today, added Armstrong. "So the real question is: When are you going to commit to it?".