He also confirmed an extraterrestrial craft crashed in Roswell, New Mexico, in 1947.
On July 4, 2008, Dr. Mitchell appeared on the "Larry King Live" program on CNN and claimed that high ranking officials, both military and civilian, have told him that the UFO phenomenon is a reality and in part a non-human gathering of intelligence of Planet Earth and the human race.
On July 23, 2008, Dr. Mitchell made the same assertions on a London radio station interview, stating that he was aware of many UFO visits to Earth during his career with NASA.
Where've I been?
On the Roswell thing, Mitchell told interviewer Irene Klotz of the Discovery Channel.
"My major knowledge comes from what I call the old-timers, people who were at Roswell and subsequent who wanted to clear the things up and tell somebody credible even though they were under severe threats and things -- this was back in the Roswell days. Having gone to the moon and being a local citizen out in the Roswell area some of them thought I would be a safe choice to tell their story to, which they did. Even though the government put real clamps on everybody, it got out anyhow."
Subsequent to that, I did take my story to the Pentagon -- not NASA, but the Pentagon -- and asked for a meeting with the Intelligence Committee of the Joint Chiefs of Staff and got it. And told them my story and what I know and eventually had that confirmed by the admiral that I spoke with, that indeed what I was saying was true."
In the same interview Mitchell discussed the Phoenix Lights incident of a few years back:
"Three humongous craft flew over Phoenix, very slowly in the middle of the night that clearly were not -- I happened to be on the phone with people out there when that happened and have had pictures of it -- clearly those were not, to those of us who know aviation and spacecraft, clearly those were not local stuff, home-grown stuff."
Of course Mitchell isn't the first astronaut to come forward with information connected to UFO's and aliens.
Astronaut Gordon Cooper (1927 -- 2004) wrote a book in 2000 titled LEAP OF FAITH. He described how he chased UFOs as an Air Force pilot while stationed in Germany in
1951. He also wrote about how he shot film of a UFO encounter from Gemini 5 that was quickly classified by President Johnson and confiscated.
In the final paragraph, Cooper wrote, "For many years I have lived with a secret, in a secrecy imposed on all specialists and astronauts. I can now reveal that every day, in the USA, our radar instruments capture objects of form and composition unknown to us."
Anyway, the media has made much fun of Mitchell and his comments, just as they have of everyone else who has ever come forth with such claims.
You can believe him or not, but me, I've always hoped some aliens would just land on our planet and say enough is enough, "We're here to straighten things out."
I mean it doesn't seem like anyone else is going to get it done.
But what if they ain't friendly, these outer space folk, you ask?
Well, Mitchel claimed our technology is 'not nearly as sophisticated' as theirs and "had they been hostile", he warned 'we would be been gone by now'.
And we're not.
The following comes from News.com au.
NASA astronaut Edgar Mitchell claims alien contact cover-up
FORMER NASA astronaut and moon-walker Dr Edgar Mitchell - a veteran of the Apollo 14 mission - has stunningly claimed aliens exist.
And he says extra-terrestrials have visited Earth on several occasions - but the alien contact has been repeatedly covered up by governments for six decades.
Dr Mitchell, 77, said during a radio interview that sources at the space agency who had had contact with aliens described the beings as 'little people who look strange to us.'
He said supposedly real-life ET's were similar to the traditional image of a small frame, large eyes and head.
He claimed our technology is "not nearly as sophisticated" as theirs and "had they been hostile", he warned "we would have been gone by now".
Dr Mitchell, along with with Apollo 14 commander Alan Shepard, holds the record for the longest ever moon walk, at nine hours and 17 minutes during their 1971 mission.
"I happen to have been privileged enough to be in on the fact that we've been visited on this planet and the UFO phenomena is real," Dr Mitchell said.
"It's been well covered up by all our governments for the last 60 years or so, but slowly it's leaked out and some of us have been privileged to have been briefed on some of it.
"I've been in military and intelligence circles, who know that beneath the surface of what has been public knowledge, yes - we have been visited. Reading the papers recently, it's been happening quite a bit."
Dr Mitchell, who has a Bachelor of Science degree in aeronautical engineering and a Doctor of Science degree in Aeronautics and Astronautics claimed Roswell was real and similar alien visits continue to be investigated.
He told the astonished Kerrang! radio host Nick Margerrison: "This is really starting to open up. I think we're headed for real disclosure and some serious organisations are moving in that direction."
Mr Margerrison said: "I thought I'd stumbled on some sort of astronaut humour but he was absolutely serious that aliens are definitely out there and there's no debating it."
Officials from NASA, however, were quick to play the comments down.
In a statement, a spokesman said: "NASA does not track UFOs. NASA is not involved in any sort of cover up about alien life on this planet or anywhere in the universe.
'Dr Mitchell is a great American, but we do not share his opinions on this issue.'