So what's it really like for astronaut Buzz Aldrin to gaze at the moon? "I don't curse at it," the 83-year-old said, referring to his cameo several years ago on the television show "30 Rock," where he yelled "I walked on your face" to the moon with Tina Fey. "Well, [I have] a little difficulty finding out exactly where we landed, but I know we were there," the second man to walk on the moon told an audience Friday night at the National Press Club. "And it really hasn't changed all that much at that distance," he said of seeing the moon from Earth.

So he doesn't brag about being there anymore, right? "Oh yeah, I do," he said to laughs.

Aldrin and co-author Leonard David were on hand to sign copies of their new book, "Mission to Mars: My Vision for Space Exploration," and talk about some of their ideas on how earthlings could make it to the red planet. "We must commit to permanency there," Aldrin argued. "I think somewhere between 2020 and 2025 astronauts selected will be asked to sign these papers that if they are successful in their careers as an astronaut they will spend the rest of their lives on Mars," he said.