Plenty More Right Stuff

John Glenn still has the same conquering spirit as he did when he made a five-hour, three-orbit trip around the Earth, reports CBS News Correspondent Sharyl Attkisson.

Although the former astronaut-turned-senator is 77 years old, he doesn't seem to give much thought to the risk of riding a rocket into space.

"You're talking about the most complex vehicle probably ever put together, and it's been safe," he says.

"There's only been one fatal accident in space. There is a risk when you're dealing with speeds and things like this, and you can't ignore that. And there will be losses sometimes. But there are losses in traffic driving to work when you come to the Senate, too."

Glenn says his main concern isn't so much for his safety as it is to make sure he doesn't "foul up" any of the experiments slated for the mission.

Glenn's experiments will use the special conditions of weightlessness to study the process of aging. Years ago, he noticed astronauts in space experience some of the same problems as the elderly, such as loss of bone and muscle mass and changes in blood flow.

After years of intense lobbying, he convinced NASA he would be the perfect guinea pig.

"I'm looking at this as a toe in the door, as a wedge toward starting what I hope will be a whole new era of investigation that can have the potential of being enormously valuable in cutting back some of the frailties of old age," he says.

Some at NASA have said Glenn's voyage is a multi-million dollar joy ride for someone who supports president Clinton, and he's getting a payback. But Glenn says that's simply not correct.

"A lot of people seem to think that I just went over to NASA one day and said, 'Hey, I'd like to go up in space,' and they said 'Oh, that's great. That's cool. Let's schedule it,' you know. This was done after peer review by the NASA scientists and people who looked into what good we could get out of this, and it's certainly not done just as any favor for John Glenn. I can guarantee you that."

Each space mission adds another layer of knowledge about living in space. NASA scientists know a lot more than they did before Glenn s first flight in 1962. Thirty-seven years later, John Glenn will return-gray and wrinkled, but amazingly fit.

With his historic shuttle mission, Glenn hopes he'll be taking one small step toward extending life for himself and for others.

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