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 offÖor 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 anymoreÖthat’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 thatÖit 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
Ö “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 wasÖguess
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
awayÖ’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 prayerÖ

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,

Peg