BIRMINGHAM, England, July 26 (UPI) -- An ex-NASA astronaut says he is still "totally sure" life exists elsewhere in the universe and earthly governments have tried to hide the existence of aliens.

Edgar Mitchell, a 77-year-old former National Aeronautics and Space Administration astronaut who walked on the moon for nine hours in the Apollo 14 mission Feb. 9, 1971, remains strong in his stance that aliens are real, the Daily Telegraph reported Saturday.

"There's not much question at all that there is life throughout the universe. I'm totally sure we are not alone," he said in an interview with Kerrang! Radio in Birmingham, England, this week.

Mitchell, who holds multiple academic degrees and has maintained his believe in extraterrestrial life for years, went on to say "we have been visited on this planet and the UFO phenomenon is real -- though it's been covered up by governments for the last 60 years or so."

NASA officials have not backed the former American astronaut's beliefs.

"NASA does not track UFOs. Dr. Mitchell is a great American, but we do not share his opinion on this issue," the space agency said in a statement.