In an interview in February 2011 Edgar Mitchell told "The Unexplained" ( 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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