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STS-113 Astronaut -- Day Three
 
Question and Answer Board

Björn from Trelleborg
Will you look back at your work and feel a personal and private satisfaction or did you go all the way for the US of A?
Yes, I think all of the people who go up work very hard to get there, and when you get back there is a sense of satisfaction in the fact that you produced something.
Cletus from Scottsmoore
Is it difficult to adapt to weightlessness and how long does it take to get used to it?
That's a good question. It takes about three days to adapt to weightlessness. It doesn't take any effort on your part; it's just that you get used to it in about three days. You've gotten past if you're going to get sick, you've gotten past it and you won't have a problem with that anymore. But after three days, you feel like you've been there for a while, you get used to weightlessness, you can move around, you can do the work, and you feel right at home.

Host: Now, once you've experienced weightlessness, do you feel like you crave it, that you want to experience it once again?
Expert: That depends on the individual. I often would have liked to experience it again. But there's one good friend of mine, he just loved it! I did too; it gives you a feeling of freedom like you've never had before.
Ariana from Warwick, Queensland
When you return to a full 1G gravity environment to you get dizzy or anything like that?
You can, because if you stand up, you have a depleted volume of blood when you adapt to weightlessness. So if you stand up quickly when you get back, you stand the chance of getting dizzy. That's corrected very quickly just by drinking water and beverages.

Host: Are there any other physical manifestations?
Expert: Absolutely. When you get back, you have sore joints, you have sore tendons, and your knees in particular bother you. I jogged a mile about three days after we got back, and I felt up and down my spine a tingling sensation like when you hit your funny bone. And that goes away very quickly. I talked to one of the other astronauts who's a physician, and he said it's just because I hadn't stimulated those nerves in so long that the brain sort of exaggerates the sensations you get from it. So, you readapt very quickly. We were scheduled for eight weeks of post-flight testing after the long Skylab mission, and after five weeks, they terminated it, because they said we'd already recovered to our preflight baseline.
David from Melbourne
It is said that bone and muscle density deteriorates during prolonged weightlessness. How is this corrected after returning to Earth?
The muscle mass recovers fairly quickly, just by doing normal exercises and walking around. The bone density is another matter. When we first got back, I'd lost three percent bone mass on Skylab during the 12-week exposure to weightlessness. They said at the time that that possibly was irrecoverable, but now they've changed their mind and they think that with proper exercises, you can recover some of that.

Host: Is there a limit on how long you can stay in space because of these effects?
Expert: There is a limit on long you can stay in space and stay productive. We don't know what that limit is. One Russian stayed up for 14 and half months and apparently has recovered. It seems that your performance starts to deteriorate after about four or five months, that is the number of hours that you are productive everyday.
David Harres from Spring Hill, Florida
My science fair project this year is about G-forces. My question is what are the G-forces an astronaut experiences at liftoff?
It varies with the booster. The shuttle is the hottest thing we have ever launched, you are pulling about 1.7 Gs when you liftoff. This is seventh-tenths more than one G. With the old Saturn booster typically one to about one point five. That's about 10 or 15 percent more where the shuttle has about 70 percent more. It leaps off faster than any of the booster we had before. I would like to fly the shuttle just to experience that. It is pretty slow going up in the Saturn until you start accelerating.
Jay from Amarillo
What is the biggest personal obstacle to overcoming weightlessness? As in the areas of digestion, etc.
Restraining your body when you are doing work. Floating around is effortless, you just push off a surface and you float. SKYLAB had the largest volume ever launched into space, 21 ft in diameter and 25 ft high. They thought we were going to get trapped in all that big volume, but all you had to do was push and you float through this volume. When you do work you have to oppose force. If you took a screwdriver floated over to a panel and put the slot blade of the screwdriver into a screw and twisted your wrist. The screw doesn't turn - you do. So you have to get used to that and restraining your body to use the torque. Using a socket wrench is the same thing. We use several different techniques and if you don't have a proper foot restraint, you can tie your legs to structure or you can have a buddy come and hold you.

Host: How long does it take to get acclimated to weightlessness?
Expert: The first day or two. It is amazing how fast you get used to weightlessness. It becomes second nature after a couple of days.
Johannes from Koeln
Where did you apply to become an astronaut? Did you just send your application to NASA? What abilities should you have before you apply for an astronaut position?
NASA opens for selection. They make an announcement. If you are in the military you apply through your respective branch of service. If you are a civilian you apply directly to NASA. NASA requirements are as follows. You have to have a minimum of a bachelor's degree, engineering, a physical science, mathematical or some related field, and they will evaluate your course of study and tell you if this will satisfy them. The truth of the matter is mission specialists are likely to have doctorate level degrees, most of the pilots selected are graduates of test pilots school. The competition is pretty severe, people have been selected with bachelor degrees but they have an enormous amount of experience in a certain area. That is another thing NASA looks for in addition to your academic qualifications is how have you performed in a work place, and how well you get along with people. That is very important.

For more information on the curriculum that you would need for astronaut qualification, biographies, training and fact sheets:
http://spaceflight.nasa.gov/outreach/jobsinfo/astronaut.html
You can also go to the JSC, Johnson Space Center home page and click on Jobs and then on Astronaut selection and there are all kinds of information there. Or you can write a letter to the JSC and ask them for the brochures of pilot selections or mission specialist selections.

NASA, Johnson Space Center
Astronaut Selection Office
Mail Code AHX
2101 NASA Road 1
Houston, TX 77058-3696
Emilio Pérez from Lugo, Spain
Dear Mr. Willian Pogue - what was the most beautiful thing that you remember when you spent 84 days in orbit with the famous Skylab orbital workshop?
Well, the sunrise is beautiful. We got 16 sunrises and sunsets in a 24 hour period. We took sequence of them and I have one mounted on my wall at home. It the sunrise is really beautiful, it comes up 16 times faster on orbit than on Earth so it really is in fast motion. But it's spectacular, and they vary, you can see the bands in the atmosphere as they shift and change and shimmer. I also loved looking at the Earth. I'm often asked what is our favorite form of entertainment when we are up there. We had an entertainment system, stereo, tapes, we had balls to play with, and a deck of cards - no one used it. Our favorite pastime was looking out the window at the Earth, and it was just spectacular! And when you are out on a Spacewalk it is even better, because you get a total panorama of the Earth. We passed a lot of our days off just looking out the window, even at night.
Patricia from Jacksonville, Florida
s it common for astronauts to experience motion sickness in space?
Yes, it is not quite motion sickness so motion sickness medicines don't work to prevent it. It is impossible to predict who is going to get it or how long it will last. You know it will be completely over in three days. I had one episode, I wasn't supposed to get sick. I'd done a lot of aerobatic flying and I was the only one who got sick on our flight. About half the astronauts have a problem with this.

Host: If you get sick once do you get sick again or is it a one-time thing?
Expert: That is a good question. The answer is, I've heard, I only went up once. They say you have to relearn it. You have to be careful the second time you go up too. If you got sick on the first time you have to be extra careful the second time and not move your head around real fast.
Paul from Brighton, United Kingdom
First of all, bon voyage to the STS-113 crew. I'm coming to see the STS-107 launch in January, so I'll see you there, but...just for interest, what age limits are there with operative astronauts, what's the youngest and oldest age that an astronaut can fly?
Actually they are not stated because of the law against age discrimination in the United States and you cannot state an age requirement. However, most of the astronauts that are selected and mission specialists are between 30 and 34, maybe 35. Pilots are usually a bit older than that and I think the youngest recently selected was 31. In the earlier days they were selected at younger ages and flew when they were younger than the ones that are flying now.
 
 
NASA's John F. Kennedy Space Center