Have you noticed the International Space Station in the western sky just after sunset? The space station has been pretty bright especially the last 12 days with the orbiter Atlantis attached to it. If you go out just after sunset, it is the brightest object in the sky, and is the width of about two hands above the horizon. So, what are they doing up there on the space station?
The recent mission for the astronauts on the Atlantis was to change out some original batteries on the station, install a communications dish and install a small Russian research room or module. The Russian module is called “Rassvet,” which means dawn. You can go to NASA.gov and learn a great deal about the space station and the Atlantis, which has just completed its last mission.
OK, so let’s think about one part of this mission for a minute – installing batteries. Most of us know about installing batteries and what happens if you wait until they die. Last Sunday I went to work at my office on the NMSU campus. School is over, students are gone, and it’s Sunday about 5 p.m. I finished what I was doing, went out to my car and it would not start. I called my neighbor who came over and jump started my car. I made a legally mad dash to Sam’s before 6 p.m. to get my battery replaced. $60 and 30 minutes later I was done.
The two guys at Sam’s were able to easily take a replacement battery off the shelf, pop open my hood, and switch the old for the new. Then they
took my old battery and put it in their recycle area for proper disposal. From where I was standing, no one attempted this job while perched off the end of a robotic arm, traveling 17,000 miles an hour about 250 miles above the earth, with their hands in boxing gloves and their face in a helmet.
Replacing batteries on the space station is a different business than it is on Earth. The batteries are on the truss, or backbone of the station. It holds the solar arrays that power the station and support life. It took two astronauts two space walks, each lasting about 6 hours, to switch out the three batteries, which would weigh hundreds of pounds on earth, and secure the old batteries for return to earth on Atlantis. The batteries store electricity generated from the solar arrays.
Back to the original question, what are they doing up there? Six people live on the station full time for months. As I said above, this mission included the delivery and attachment of the Russian laboratory. The laboratory is one of many functioning laboratories on the station. The laboratories conduct experiments in a medically unique research environment called microgravity. For example, microgravity changes how disease-causing organisms, called pathogens, behave. There is an ongoing experiment to determine if we can develop vaccines in microgravity for disease prevention . We know some of these pathogens will not grow like they do in microgravity. We don’t know if they will be useful for manufacturing into vaccines yet.
Another experiment will determine how balance is affected by changes in skin sensitivity before and after spaceflight. This experiment will examine skin sensitivity on the sole of the foot. As we age, maintenance of balance is a physical skill necessary for ongoing health. In microgravity, astronauts do not stand nor do they support their full weight during the entire duration of their time in space. Some astronauts spend months on station. We will learn how small sensors on the soles of the foot might help us train our bodies to keep our balance as we age or recover from surgery.
I dropped a 10 pound weight on my foot Thursday night while weight lifting. Tough week for me. I run most days and also lift weights daily. I know the importance of balance during my runs and I know because I am favoring my left foot; the rest of my body is compensating. This experiment is one I will be interested in following. I look forward to the safe return of Atlantis. I am grateful to our country and NASA for this wonderful ship that will now retire. And, go out and look to the west and imagine.