Timehost:Hello! Welcome to the TIME room! Our guest this afternoon is a man who can relate very well to what John Glenn is going through right now. He's Charles Walker, three-time shuttle astronaut. He was a payload specialist, which is the title that John Glenn holds on the current mission. He's also President of the National Space Society, co-host of our chat this afternoon. He joins us from the site of the launch at Cape Canaveral. Welcome, Mr. Walker!

Charles Walker: Thank you.

Timehost:Let's go with the first question...

Appollinia asks: What will Glenn actually do in space?

Charles Walker: Well, John Glenn will be doing medical research on conditions that affect all of us as we age. But these conditions also affect astronauts and are exaggerated by weightlessness. So studying these conditions in a man of his age will hope to give us new insight into these conditions. These conditions include bone loss, muscle loss, blood chemistry changes, and sleeplessness.

ryguy14850 asks: What kinds of experiments are planned to advance our knowledge of gerontology on this mission?

Charles Walker: John Glenn and some of the other astronauts as well will be test subjects, contributing blood, and urine samples to watch for blood chemistry changes as the body adapts to weightlessness. In addition, there has been a nuclear magnetic resonance imaging test of John Glenn before flight to look at his bone structure and bone growth, and that will be completed after flight -- to look at how eight days of weightlessness have changed, or have not changed, his body. In addition, his brain waves will be monitored -- his heart, his lungs they'll be looked at to understand how weightlessness affects a senior citizen. And since the effects of weightlessness are like the aging process, it's hoped this will give us new insights.

Beaniebaby01 asks: Will the conditions affect Glenn's aging? Will he come back feeling about 90 years old?

Charles Walker: First of all, let me say that's a good question. Because weightlessness makes everyone feel weaker when they're back on the earth. And that will be the same for John Glenn. So as where the 35-year-old astronauts may feel 50 when they come back, John may feel at least 80. But, all this weakness goes away within a couple of days.

DASAL_666 asks: Why should Glenn get the opportunity to go up and not me?

Charles Walker: Let me say that since shuttle space flights require a lot of discipline, experience at flying, and a real scientific purpose, not all of us can meet those conditions. And in this case, John was the first man to come forward with his background, experience, and a good scientific reason to get the seat. So good luck in coming up with new ideas!

yyddf asks: Is the scientific gain of sending Glenn into space really worth the expense??

Charles Walker: My answer is, I think there may be some question about whether it is, but just like any other science research, we won't know the true worth or value, for years or maybe decades. But we must try everything we can to better understand both human health here on earth and human adaptation to space. But science is only half the reason Glenn is going. The other half is he's going for all of us who remember him going or have read of him going on the first orbital flight and would have liked to be with him then, or would like to be with him now.

bddill_98 asks: What time is liftoff? Good luck, John Glenn!

Charles Walker: Right now, we're standing at the edge of the water about 3 miles from the launchpad at 39B. And we're standing about 50 feet from the big countdown clock. We're at a pre-planned hold point in the countdown, and all systems are still "go", we're just waiting to start the clock in order to hit the pre-planned launch time. That's at 2 p.m. eastern time. And the crew has been on board for about an hour and a half, lying on their backs on hard aluminum launch couches, in their pressure suits. And some of them may be wishing they didn't have that last cup of coffee and breakfast. I know I did when I flew the first time. kandie911 asks: How confident do you feel about this mission?

Charles Walker: I feel very confident about it. I flew on the first flight of Discovery, and that was 24 missions ago for this orbiter, and I think she's an excellent spacecraft. I have the highest confidence in both the shuttle and the people who put their blood, sweat, and tears into preparing it to fly. The NASA crew is expertly trained, highly skilled, dedicated and determined to make a successful mission. And John Glenn is a past master at space flight himself. While we may call him a senior citizen, I think he's still got the right stuff, to make a complete success of this mission.

TheMusicMan01 asks: What do you think John is thinking right now?

Timehost:By the way, launch is going according to routine! The clock is on hold -- but that's all according to schedule.

Charles Walker: Right now, I would guess that John, like the other crew members, are going through their last-minute checklist, refreshing their memories of emergency procedures in the unlikely event that something happens on the launchpad that they don't want to happen.

Timehost: The launch clock is now on...about T-minus 12 minutes.

Charles Walker: And I imagine that he and the other crew members, like myself at this point in the countdown, are just very anxious to get off the ground. As well as feeling a little back ache, probably.

aaaaaaaaaahhhhhhh asks: Will they be able to take off because of the weather?

Charles Walker: That's a short answer. The weather is perfect, not a cloud in the sky. The winds, both above and below, are well within desirable conditions. And the whole world is ready to see Discovery launch, so we're going.

Timehost:T-minus 11 minutes and counting....

sleepydude98again asks: How many g's do you feel when the shuttle lifts off?

Charles Walker: Good question. At the instant that the shuttle rises from the launchpad, the crew will feel half-again as heavy as they normally feel, one and one-half Gs. They will accelerate to 2 Gs as the boosters burn out in 2 minutes. From there, they accelerate up to 3 Gs and for the last two minutes of their 8 minute launch, they'll feel 3 Gs, three times normal weight. And then, within two seconds, they'll go from three times their weight to feeling no weight at all.

Timehost: T-minus 9 minutes or so and counting

Hellonwheels99 asks: What's it like to blast off...how does it feel??

Charles Walker:Well, I would refer back to the previous question. You feel a lot of acceleration as increased weight, and during the first two minutes, there is a tremendous amount of vibration. But overall the experience is like riding the hottest rollercoaster in the world.

Mr_David_da_man asks: How long does it take to leave the earth?

Charles Walker:It takes 8 minutes to climb from the launchpad to the shuttle's orbit more than 300 miles up. But the atmosphere, we leave it behind, within three minutes.

Timehost: It's routine...but the countdown is now being held at 9 minutes.

michael_virgo asks: What is it like to up in space?

Charles Walker: Well, that's a question that requires a lot of words, and I'll try to be short. The feeling is many, many things. It's emotional, it's psychological, you feel a physical presence of the whole world beneath you. The view of the blue and white colored earth is just beyond description in its beauty. The black depth of space is also beyond description, it draws your eyes into it.

Timehost:Right now, they've held countdown at nine minutes...what's going on?

Charles Walker: We're going to get a reading on that momentarily...

Charles Walker: Okay, the reason for the delay: instruments showed a slight drop in cabin pressure in the crew compartment, and they're trying to determine why they got that indication. I might add ... that same circumstance happened on my first flight attempt, and, after the flight controllers couldn't figure out why, they asked all the crew to check the valves in the cabin. And I checked the one behind me on the wall, and it was open. It had been left open by the close-out crew. So I unbuckled, closed it up, and we were ready to go.

Timehost: Who's the one who makes the final call about whether they go ahead or not?

Charles Walker: Final go decision is made by the launch director here at Kennedy Space Center.

NCG25 asks: Why is the launch time window so important?

Charles Walker:When you're trying to rendezvous with another spacecraft already in orbit, the orbital mechanics for objects moving at 18,000 miles per hour leave very little room for error. So, for instance, when the space shuttle has been launching to rendezvous with the Russian Mir space station, they had launch windows of less than five minutes. But today's launch window of 2 1/2 hours is so relaxed because we're not rendezvousing with anything in orbit. We just don't want to wear out the crew waiting on the pad.

snow_cherub asks: what is wrong with the cabin vent alarm going off?

Charles Walker: Stand by ... we' re listening to words from launch control now. They're about to make a determination whether they can pick up the countdown or not.

Charles Walker:Okay, they have picked up the countdown again. So it's 8 minutes and 50 seconds and counting. Apparently, the problem was determined to be no problem, or has been repaired.

Timehost: We're on the edge of our seats!

Charles Walker: We're on the edge of the water ... so we're all on the edge here!

zachlsd25 asks: Can an anti-gravity atmosphere give you headaches?

Charles Walker: Gosh, hard question cause I don't know what an anti-gravity atmosphere is. I will say, though, that when floating in space, without gravity, headaches are a common symptom for a few hours or a day or two, when one is adapting to the feeling of weightlessness. But since there's no such thing as artificial gravity just yet. I'm not sure if that answered the question.

VeronicaR5 asks: what is the last minute that the countdown would be stopped?

Charles Walker:The countdown could be stopped even at 1 second to go.

Timehost: We're now at T-minus 6 minutes and fifteen seconds

Charles Walker: On my first flight, on our first launch attempt, my launch was stopped with two and one half seconds to go. It was stopped because computers detected a problem with one of the shuttle engines. But the countdown can be stopped only down to zero, when the solid rocket boosters ignite. Once they are ignited, the space shuttle is going somewhere.

Timehost: T minutes 5 and a half minutes and counting

Charles Walker: Because they cannot be turned off.

Timehost: Why are they holding the countdown at 5 minutes?

Charles Walker:I haven't heard specifically from here yet, but it wouldn't surprise me if it was an aircraft. It has happened several times before, someone wants to get a better view than everyone else. It's confirmed now. An unidentified aircraft in the area. In the past, there have been several instances of private pilots wanting to get in closer than allowed. By the rules, no aircraft is allowed within something like five miles.

WOPPA_234 asks: Have you ever had a false alarm on board?

Charles Walker: Oh yeah. False alarms do happen. And, in fact I'll give you a dramatic example of a false alarm. On my first flight again, we were having dinner, the seven of us, I think it was the fifth day of the flight, and all of a sudden we heard a knocking on the side of the spacecraft. It sounded like someone knocking at the door, several wide-eyed astronauts went looking for the cause very quickly and it took about 10 minutes to determine that it was our communications antenna that was banging periodically against the side of the spacecraft because of a component error, a problem with the equipment. Unexpected alarms like that give you a moment of chills, but everyone is trained to respond in very specific ways to immediately find the cause and correct it. And they almost always make for good stories later.

CyberAngel71 asks: Charles....are you ever afraid of takeoffs in the shuttle?

Charles Walker: Answer is yes, always a little afraid. I don't think a person would be human and not be at least a little afraid of sitting on 4 million pounds of high explosives. But it is expert training, and trust in our scientists and engineers, contractors and civil servants, that give us the faith to go ahead with not one flight, but many flights, if we can do it. And then of course, there's always the expectation, of thrills and sights that very few people have ever seen. And who could resist a chance to do things like that?

Smilieo_17 asks: If the countdown is stopped with 2 seconds left, do they add additional time to the countdown when it's resumed?

Charles Walker: That's a good question. The answer is no. Once the countdown has gone past, 31 seconds, and is stopped, they cannot restart the countdown without re-cycling. Going back at least 24 hours in the countdown.

Timehost: Any more news on the delay?

Charles Walker: No, not yet.

Timehost:We're about 11 minutes past the scheduled launch time.

Charles Walker:They're still shooing the airplane out of the way. No other identification on the plane just yet, but you better believe the FAA will have the number on the pilot's plane, and his license.

snow_cherub asks: Shouldn't the air space have been secured long before lift-off?

Charles Walker: The answer is yes. But we don't shoot down private planes, we just take the time to shoo them out of the way.

kelley_mac asks: What is the best part about going into space?

Charles Walker: There's no one best part, there are many great things. The view of the earth, the freedom of weightlessness, the unobscured view of the universe, and of course the most exciting kind of flight yet to be invented -- rocket flight and space flight. And I might add that there's also the many, many friendships and meetings with hundreds of good people who help prepare each shuttle flight. To let you know, the countdown has picked up again. It's at T minus 4 1/2 minutes.

snow_cherub asks: There have been things that have gone wrong before with missions, what new precautions are followed today so that mistakes won't happen again?

Charles Walker: That's a good question, but hard to answer in short form. Because every problem is investigated, solutions are created, and trained for so every problem should not happen again just as it might have happened once because we are ready for problems we've had before. We're at about T minus 2 1/2 minutes so we should probably get ready for launch. At this point, the crew is just closing the visors on their helmets, pressurizing their space suits, checking their straps and their connections, the commander and the pilot are watching all of the engine and tank readings. And very shortly the launch conductor will wish the crew well, and tell them that they can expect a good flight because we're ready to go. T minus 2 minutes. At this point, everyone is moving as close as they can to a location where they can see the rocket. The thing that is caused the external tank beanie has just been retracted. That's a good sign. That's one of the last big outside events around the pad. before liftoff. And the next big event should be the withdrawal of the crew arm, the access arm to the closed hatch.

Timehost:One minute to go.....

Charles Walker: The arm can be moved back within seconds if needed for a quick crew escape and the arm has just been retracted. T minus 30 seconds. We're into the last few seconds of the countdown.

Timehost: 10...9...

Charles Walker: Here we go...

Timehost: 3..2..1

Charles Walker: We've got liftoff!!!!! Discovery STS 95, John Glenn is on his way back into space. The sound has just reached us from 3 miles away...

Charles Walker: The earth is shaking beneath us My pant legs are flapping with the breeze from the rockets. They're on their way! Everything's good. It's a beautiful launch. Everything looks good to this point! It looks like a white sphere of streaking flames, shrieking into outerspace It's an extraordinary experience to see one of the most powerful human machines leaving earth behind.

Charles Walker: The crew is now experiencing 2 Gs of acceleration. The solid fuel rockets will be kicked away at a about two minutes into the flight. They'll be recovered off the coast of Florida and reused again The shuttle is traveling at 2,500 miles per hour and we've just had separation of the rocket boosters. The crowd here is acknowledging the success of the first stage of the flight. Three shuttle engines are blasting the rest of its way into orbit. It's now doing 3,500 miles per hour and accelerating. We can still see it as a bright point of light. The rocket boosters are visible as white dots falling away in the blue Florida sky.

Michael_Schumacher_ says: ITS FANTASTIC

CyberAngel71 says: Tell John Glenn and the rest of the crew God Speed!

Charles Walker: What we see is actually extremely bright, almost as bright as the sun, the rocket engines burning over 5 tons of propellant a second.

CyberAngel71 says: Please tell John Glenn that I watched him when I was in the fourth grade and now I am so proud to say my children and grand daughter are watching him now.

Charles Walker: That's a beautiful refrain. I watched John Glenn go too, I skipped school to watch John Glenn go the first time. The launch control indicates that all three main engines are still propelling successfully. Looks like we've had a great launch, though it's not over yet. We've got about three minutes until they're into orbit. The crew should be experiencing about 3 Gs of gravity, pushed back into their seats. The crew is very careful to avoid disorientation from moving your head and disturbing your inner ear.

Charles Walker:Your arm feels like it weighs about 50 pounds. The shuttle is now going about 7,500 miles per hour. All systems are going well, the launch crew is saying. Right now the crew could abort, if they had a problem and had to launch a tank, they would land across the ocean in Banjul, Morocco. And they continue to accelerate on their way to space.

Timehost:Not bad!

Charles Walker: Right now John Glenn is probably glad he's only pulling 3 Gs and not 7 1/2 Gs like he did 36 years ago atop an Atlas rocket. We have made progress in the space program.

missy23_14 says: This is pretty cool.

maggieduffy says: This time my class is skipping writing to watch Glenn.

Charles Walker: Well, I'm sure you'll have something great to write about when you get back to class work. This is the kind of event we can all remember for years to come, and rightfully so. I think it shows how successful our space program is, how it can make dreams come true for old and young, and with the thousands of products and services that have come from space technology, it's a tremendously positive investment by the American people.

Michael_Schumacher_ asks: ITS A MIRACLE

Charles Walker: It's a miracle! Michael is right. It was more of a miracle when John Glenn went up the first time, but all the same, it's a wonderful event... Okay, the space shuttle is in orbit. The external tank, the big fuel tank, has been jettisoned, it's empty. Right now the crew is weightless, and I imagine right now there's a bunch of Texas "yahooing!" and congratulations being passed among the crew. One of the astronaut pilots on a previous flight said that when his shuttle reached orbit there was so much yelling of joy, that he felt like he'd never been surrounded by so many children before.

maggieduffy asks: What happens to the big things that fall off of the shuttle as it takes off? My third graders would like to know

Charles Walker: For Maggie and her third graders, I'm sure you're thinking of those big solid rocket boosters, they burn out and fall off, And they fall into the Atlantic Ocean, 15 miles out to sea. but they're on parachutes, so they are picked up by large ships brought back to Cape Canaveral, and reused again. I'm looking up at Jake Garn, a senator who was on my first flight! He's down here watching the launch and making some commentary with another communications service. There were dozens of astronauts here today at the press site of Kennedy, watching the launch and commenting on the launch.

lorlee_k asks: Which direction is it actually going in besides up?

Charles Walker: Good question because it's going up and to the southeast from Florida. And southeast direction will put it into an orbit that carries it about 28 degrees of latitude above the equator, alternating with 28 degrees below the equator. In other words, it crosses the equator twice in one circle.

king_fish22 asks: Was the roll performed exactly as planned, or did they have to correct?

Charles Walker: They performed the roll maneuver right after liftoff as scheduled. And that put them on the correct path to orbit.

Looburger says: I'm from South Africa and don't really know John Glen, but I'd like to say I still think every launch and space mission is something amazing!

TARDIS_TRAVELER says: THAT WAS BEAUTIFUL!!!!!!!

Charles Walker: Well let me just add that I agree with you all, and I hope you all get a chance to see one live, at the Cape some day. Because they're almost indescribable in person.

Turd_Machine98 asks: Why is this mission historical?

Charles Walker:This mission is historic because it carries an original space explorer back into space after three and a half decades. The first American to have orbited the earth at a time when it was still uncertain that it could be done safely. And this man was denied the chance to go back because he was thought of by the President as a unique, invaluable national hero. And now, as a 77-year-old elder citizen, he gets to ride back into space for that second trip. And what's more historic is that he is 77 years old. And he's still got the right stuff.

Timehost:Before we close, Charles, do you have any further thoughts you'd like to share about today's historic liftoff?

Charles Walker:Well, yes. I just want to thank the audience for listening in, asking interesting questions, and I hope that you'll all take up the subject of space find an opportunity to tell your congressman or senator or if you're in a country other than the United States, encourage your government to join in the next big human space program, the Space Station. And let's all work for a better tomorrow, through understanding each other, working with each other, and exploring space for the benefit of all of us here on the home planet. Good bye and hail Discovery!!

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