From: Johnson Space Center
Posted: Sunday, August 17, 2003
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).
// end //