"The great word to describe that day was uncertainty. No one knew if it would work," the scientist told ABC13. "At every moment, there was success. There was a sigh of relief."
Neil Armstrong was the first and Gene Cernan was the last to leave the lunar surface.
UNITED IN SPACE: A space enthusiast is on a quest to erect a statue of the first man on the moon in Russia and at Space Center Houston.
Ohio police say a rare gold replica of the lunar space module has been stolen from the Armstrong Air and Space Museum.
Thousands of photos from the manned Apollo missions were curated and released in a new Flickr gallery on Sunday.