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IMAGE: Expedition Five Flight Engineer Peggy Whitson
Astronaut Peggy A. Whitson tries on a spacesuit during training at the Johnson Space Center in Houston, Texas.

Expedition Five
Letters Home #5

By Astronaut Peggy Whitson:

Dear Friends,

Last week Valery and I spent a couple of days practicing robotics operations. One of the unique things about the station robotic arm (called Canada 2 or the "Big Arm") is that either end can be the base or the end effector that is able to grapple various fixtures that are installed on structure. Since the arm was delivered to station, it has been operating from the same position on the laboratory. Valery and I performed the "step-off," and now the arm is based on the Mobile Base System (MBS) that was delivered on UF2 (STS-111). Carl Walz (Expedition 4) and I installed the MBS onto the Mobile Transporter, using the station robotic arm. The Mobile Transporter is our "train" that will carry the MBS between different worksites along the length of the truss. At completion, the truss will be just over the length of a football field, so we will need the arm to be mobile in order to service all parts of the station. As a part of our practice last week, and to make sure that the arm performed as we are anticipating for the upcoming tasks, we ran though each of the maneuvers that will be required for the installation of the next truss segment. (This truss, called S1, will be brought up by the next shuttle.)

We do all these robotics tasks with camera views. The limitations we have now are that there aren't that many camera views and none of them are much good at night (camera lighting is only good for about 2-3 meters). You might not think this is a big deal, but one crew got the arm within 3 inches or so of an antenna. I don't really want to get famous as the person who knocked an antenna off…or hit anything else for that matter! It is this fear of infamy that I have to use to stay alert while working with the arm. We've done so much computer simulation of these robotics tasks, and the fact that we don't have a window to see what we are doing with the arm, makes it easy to forget that there really is an arm out there. In fact, during UF2 when Valery and I were using the arm to support the EVA crew members, he was asking me about the light/shadow we were seeing in the camera view. I told him, "It's not a simulation anymore…that's real!"

Last week we did our first experiment in the glovebox, in spite of the fact that SAMS (space acceleration measurement system) was not cooperating. The temperatures inside the experiment chamber got up to 700 degrees C. I was showing Valery the temperature readouts, and he said we should grill some meat on that…it wouldn't take long!

Each morning the ground sends us up a daily summary of what we are supposed to be doing, with additional information for the tasks that are not found in the procedures. At the end of each summary, they include a quote for the day and a comic. One of the quotes for the day last week was an interview question that I had received the day before … "What question have we not asked you that you would like us to ask?" I couldn't come up with a question (or an answer) for this one. But believe it or not, this isn't the first time I've been asked this.

Last week I got to photograph the soybeans. This experiment is growing in a completely enclosed environment, so I hadn't been able to see the progress of the growth. The ground has been watching via video downlink, and they wanted me to check and see if the soybeans were flowering. They were surprisingly tall, about 12", filling the chamber and then bending over at the top, but not yet flowering. It was surprising to me how great 6 soybean plants looked. I assumed it was because I like plants, but Valery and Sergey had the same reaction and even wanted their photos taken with the plants. I guess seeing something green (that stuff we re-hydrate that they say is broccoli doesn't count) for the first time in a month and a half, had a real effect. Sergey, of course, thought we should eat them as a salad. I managed to save the science and get them into the rack before he was able to eat them! From a psychological perspective, I think it's interesting that the reaction was as dramatic as it was…guess if we go to Mars, we need a garden!

On Monday and Tuesday of this week, Valery and I were working on the carbon dioxide removal assembly (CDRA). Since the launch of the laboratory module, this particular system has not worked entirely correctly. They have used software patches to partially work around the problem. (The Russians have the prime CO2 removal system, ours is the backup.) But the folks on the ground decided that we should remove and replace the sorbent bed with the faulty valve. This bed is about 4 feet x 10 in x 10 in, which wasn't a big deal, it's just that all the components of the removal system are located on the front of this bed. So in essence, we had to tear the whole thing apart, replace the bed and then put the system back together. About 4 hours into it and we were not past the easy part of getting the bed out of the rack, and I'm thinking, we should have returned the whole rack to the ground for repair.

Once we finally got the bed out, things went a bit smoother. Putting it back together was challenging, since we had to route the electrical harness, the gas hoses and the thermal loop hoses in just the right way in order to fit it all back together. Each time we thought we had it right, we would get to the next step and have to backtrack three steps to reroute another cable. I considered it a success from the fact that we did not end up with any spare parts (I'm hoping none floated away…'cause I don't want to go back in there). The real test of course will be when they turn it on in a couple of days. Say a prayer…

At one point, the ground was getting video while Valery and I were struggling with a hose that had come undone behind the partially rotated rack that contained the CDRA. The ground was calling us with instructions, but our hands were full. The ground did not have a good view of what we were doing, but they could see my leg sticking out from behind the rack. They said if you "copy" these instructions, wiggle your right big toe. I wiggled my toe, and we could hear the ground controllers laughing and I was laughing so hard that Valery insisted that we stop our work so that I could explain what happened.

Take care,

Curator: Kim Dismukes | Responsible NASA Official: John Ira Petty | Updated: 11/15/2002
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