Ed Lu’s Journal: Entry #9: Day in the Life
This
week I thought I’d write about what a typical day is like.
To do that I’ll just run through what is on our schedule this
week, and you can get a pretty good feel for what keeps us
busy. First off, we live on Greenwich Mean Time (GMT) — which
is a time zone roughly halfway between Houston and Moscow,
where our two main control centers are located. So when we
wake up (at around 7:00 GMT), it is 2 in the morning in Houston
and 11 in the morning in Moscow. You can’t live by the daylight/nighttime
cycle up here since we get 16 sunrises/sunsets a day! By the
way, to get to sleep at night we have to cover the windows
to keep it dark in here, so right after getting up one of
the first orders of business is to uncover the windows.
The next
order of business of course is using the bathroom. The toilet
is operated by air pressure. A fan does the work that gravity
does on the ground. Urine is sucked inside the toilet and
is collected in a 20-liter container. When these are full
they are discarded in the Progress. For collecting solid waste
the toilet has plastic bags you place inside, and air is sucked
through tiny holes in the bag. Everything gets collected in
the bag (hopefully) and the bags self-close with an elastic
string around the opening. You then push the closed bag through
a hole into an aluminum container, and put a new bag in place
for the next person. The toilet works great, although we did
have to do some plumbing repairs last week when the fan unit
died.
Next
up is breakfast, followed by our daily 8 a.m. planning conference.
This is just a short 15-minute chat with the control centers
in Houston, Moscow, and Huntsville (where our payload control
center is located) to review the plan for the day and answer
any questions we or the ground might have. Then we get started
on the day’s work. This week in the mornings I’ve been working
on an experiment that looks at how metal alloys crystallize
as they cool. The structure of metals is composed of lots
of very tiny grains, and the size of these grains affects
the strength and other properties of the metal. We already
have a pretty good theory of how this process of crystallization
happens as metals are cooled from a liquid state. The theory
is complicated by the fact that on the ground, liquids of
different temperature tend to mix themselves very well in
a process called convection (the same process that you can
see if you look in a pot of almost boiling water, you can
see rising columns of water whose temperature is slightly
higher than the average). Up here that effect doesn’t happen
since it depends on gravity making less dense liquids rise.
So the hope is that it will be a little easier to understand
how the crystallization process occurs if observed up here
rather than on the ground. Perhaps this will give us some
insight into how to further refine the models we use for predicting
the properties of metal alloys. Meanwhile, over in the Russian
Segment of the Space Station Yuri has lately been working
on an experiment that looks at what are called plasma crystals.
Inside a sealed chamber are small plastic spheres that are
given an electric charge so they all repel each other. What
happens is that they each try to get as far away as possible
from the other particles, but since they are in an enclosed
volume they end up forming a regular lattice. It’s an interesting
physics experiment, and it can’t be performed on the ground
because the weight of the spheres makes these structures collapse.
Yuri this week was looking at waves that propagate in these
lattice structures. There are a whole host of other experiments
up here, ranging from medical investigations with us as the
subjects, to experiments on magnetized fluids, to ultraviolet
observations of lightning storms.
We also
have general housekeeping-type activities scheduled. These
are things like cleaning filters, doing periodic inspections
of our emergency equipment, sampling our water supply for
contaminants, vacuuming out the air ducts, etc. These regularly
scheduled tasks are something like household chores back home.
We each usually have a couple of these a day. Today for instance,
I’m scheduled for cleaning air ducts, rebooting the computers,
and making some changes in our checklists.
In the
morning, we also have the first of our two exercise sessions
for the day. After sweating on the treadmill or bike, it is
time to clean up. We don’t have a shower up here (the water
wouldn’t go down through the drain anyhow), so we wash using
no-rinse soap and shampoo and a towel. It is the same stuff
they use in hospitals for bedridden patients, and it works
really well. That being said I am looking forward to a long
hot shower when I get home!
We usually
have a break for lunch scheduled around 1 p.m., then we get
back to work. This week we’ve been doing some maintenance
and troubleshooting work. One of our spacesuits has had a
cooling failure, and without cooling it is not useable for
a spacewalk. To keep from overheating inside the spacesuit,
there are small tubes that run throughout the suit with chilled
water pumped through them. When we tested the suit a few weeks
ago, there was no water flow in the tubes, and the temperature
quickly rose above 100 degrees inside the suit (which made
it feel like standing in a parking lot in Houston in July!).
There are a whole bunch of reasons why this could have happened,
and we are ruling them out one by one until we figure out
what is wrong. Luckily we have a spare suit, and the other
day we configured it so I could use it in case we would need
to do a spacewalk. Some of the other repair work we’ve done
this week was on our water recycling equipment. We humans
exhale water vapor (breathe on a cold window to see that),
and this water is condensed out of the air using something
similar to an air conditioner. The water is then purified
and we use it for drinking water. We needed to replace one
of the catalytic water purifying columns (it is a bunch of
tubes filled with a resin that absorbs impurities in the water).
The other major repair we’ve done recently is on the treadmill.
We replaced some of the bearings because the engineers found
that during tests on the ground these bearings can fail.
In the
afternoon we have another scheduled exercise session, then
we have another short conference with Houston, Moscow, and
Huntsville at around 7 p.m. to wrap up any questions from
the day’s work. Following that is dinner (always a fun time!),
and then we have a few hours of free time before bedtime to
do what we choose. I spend this time working on some science
experiments of my own (I’ll describe those in a later installment),
sending and reading e-mails from home, and taking photographs
out the window. There is also a small electronic piano up
here that I like to tinker around on. The other night was
amateur barber night here, as we were getting a little shaggy
and it was time for a haircut. These hours go by really quickly.
Just like at home it seems there are never enough hours in
the day to get all of my personal projects done! Finally it
is time for bed; I have a sleeping compartment in the Laboratory
Module, and Yuri has one down in the Service Module. They
are each about the size of a phone booth. My sleeping bag
is mounted up on the wall, and when I finally get to bed I
have no trouble at all falling asleep. All in all, we work
about 10 hours a day, with a half-day off on Saturday and
a full day off on Sunday. Although when you live in your office
it is a little hard to draw the line between on duty and off
duty – we are often called by the ground to perform some task
when something goes wrong and they need our help on some procedure.
By the
way, the ground doesn’t micromanage our time, and in fact
most things on our schedule are very flexible. Only sometimes
does a particular task need to be done at a particular time,
and if so it is called out that way on our schedule. Otherwise,
we are free to move tasks around during the day as we see
fit, although the order that Mission Control lays it all out
in the schedule usually works pretty well. Mission Control’s
job is to see to it that the required tasks are prioritized
and that there is enough time to do the tasks, as well as
doing any needed coordination. Our job is to get all the tasks
done. We often make suggestions for optimizing things, and
we work together to make operations more efficient the next
time. This is a very good system – think of how it would work
if you had somebody several thousand miles away try to organize
your day at the office down to the minute. It wouldn’t work
very well, since they are not there to make real-time decisions
on what is best to do at any particular moment. You have certain
things you need to get done each day, and you may juggle things
around depending on how things are going. We do the same up
here. Think of this as one big experimental vehicle – which
it really is because it is the first of its type and one-of-a-kind.
Our day-to-day operations, including repairs and maintenance,
are giving us experience that will hopefully help us design
and operate long-duration missions to asteroids and to Mars.
Sometimes the lessons we learn are how to do things, sometimes
the lessons are how not to do things. But we, as well as the
engineers, managers, and scientists, are learning things that
can help us leave low Earth orbit and explore.
Okay,
so our haircuts aren’t so good! What do you expect? The thing
in Yuri’s left hand is the vacuum cleaner hose (to suck up
all the hair).