As the second man to walk on the moon, Edwin "Buzz" Aldrin has cemented a spot in history, but the now 79-year-old has spent much of his career looking to the future.
In the decades since the moon landing, Aldrin has lectured and written extensively about the country's future in space. He retired from NASA in 1971 but continued to work on space exploration, proposing a plan to reach Mars and receiving three patents for a modular space station.
He has also penned several books, including an autobiography, "Return to Earth."
In an interview with Chaikin for "Voices From the Moon," he shared the difficulty in articulating his experience.
"I'm not really sure how a layperson reader is going to grasp whatever words are going to try and describe this. I've felt totally inadequate in ever trying to do it with spoken words," he said.
In a rare show of violence, he punched filmmaker and skeptic Bart Sibrel in 2002 when Sibrel challenged him to prove that he actually went to the moon.
Pete Conrad wasn't the first to walk on the moon, but some remember him as the first to dance on it.
In "Rocketman," a book about the astronaut's "incredible ride to the moon and beyond," his wife Nancy Conrad and Howard A. Klausner, describe the third man to walk on the moon as an adventurous, free-spirited space cowboy.
As the world listened to Conrad's first moments on the moon, he hummed. And then he shouted.
"Whoopie! That may have been one small step for Neil, but it's a long one for me!" he roared.
Conrad was selected as an astronaut by NASA in 1962 and traveled to the moon in November 1969 as the commander of Apollo 12, the second lunar landing.
Years later, in an interview with Chaikin, he said, "I remember thinking I got to go to the moon. And I can also remember thinking, it's going to change a lot of people, to do that. … I thought very hard about that I didn't want it to change me… [And now] I don't think it changed me."
After 20 years of service, including 11 as an astronaut in the space program, Conrad retired from the U.S. Navy to begin a career in business. He accepted an executive position with the American Television and Communications Corp., a cable television company in Denver, and later became vice president for the Douglas Aircraft Company.
In July 1999, at age 69, Conrad died after a motorcycle crash near Ojaj, Calif. He was survived by his wife, three sons and several grandchildren.
In his book, "Carrying the Fire," fellow astronaut Michael Collins describes his courageous and notoriously puckish colleague as "One of the few who lives up to the image."
In 1969, Alan Bean touched down on the Moon. But through his paintings, the astronaut cum artist says he tries to extend the moment.
"Our time on the Moon ended much too quickly and, in the years since then, I have created paintings to try to capture the feeling of our Apollo 12 mission, as well as all the other the Apollo missions, too," he says in an introduction on his Web site.
After 18 years with NASA, in 1981, the Apollo 12 moonwalker decided to pursue painting full-time to share the sights no other artist had ever seen. But he approached it the way he might a moon mission.