In an interview in February 2011 Edgar Mitchell told "The Unexplained" (theunexplained.tv) mankind would have to explore other planets because one day the sun will burn out and our species may need to find a new home. In the show, he also told British host Howard Hughes he believes aliens have been visiting earth for a very long time.

Dr Mitchell thinks thinks are different species - some who have our best interests at heart and some who may not. And he believes there are people - some in and around the space programme and bound by confidentiality agreements - who will one day bring forward more evidence. Dr Mitchell also discussed his ongoing concerns over the "sustainability" of earth's resources.

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