ISS Crew Answers: Expedition Five

From: Luis Humberto Perez Leyva, Guadalajara, Mexico, Age: 17

Question: Can you speak about the chemical or biological experiments in the International Space Station? Thank you very much, and I wish you good luck.

Whitson: We have a wide range of experiments involving chemical and biological properties. Things like protein crystal growth of many different types of materials -- drugs, proteins involved in disease, etc. -- don't require a lot of interaction, while other experiments like the pulmonary function tests that we perform on a regular basis and before/after EVA require a lot of crewmember participation. We have also conducted experiments involving various techniques to microencapsulate anti-cancer drugs and DNA, using the lack of gravity as a variable to better understand this process. Inside our newly activated Microgravity Sciences Glovebox, we will be conducting various melting/resolidification experiments, again using microgravity as a variable in order to better understand these physical processes that are involved in generating materials for everything from computer chips to shock absorbers. In our large variety of experiments, we are also examining the growth of soybeans and liver cells.

From: John-Philip Faes, Strombeek-Bever, Belgium, Age: 29

Question: Could someone tell me what patch the astronauts wear on the backpacks of an ISS based EVA? I know the astronauts wear the mission emblem and the EVA patch, but the patch on the back of the backpack I don't recognize.

Whitson: I had to go look at the back of the U.S. suit to remember which patches are there. There is, of course, the U.S. flag and below that the NASA emblem. The flag of the country of the crewmember doing the EVA is worn on the left shoulder and the EVA emblem on the right.

From: Paul Yonna, Perth, Australia, Age: 50

Question: I understand that you do medical measurements on the station. How do you weigh yourself in zero gravity?

Whitson: We weigh ourselves with a Russian-built device called the body mass measuring system. It calculates inertia as it moves a mass back and forth on a calibrated spring. It's very simple system, but seems to work very well. After we calibrate the spring, we climb on the device and release the spring. Our mass is calculated from the inertial forces on the spring.

From: Joseph Hill, Wantage, England, Age: 14

Question: Hi. I was wondering -- after seeing a video about the ISS -- how cramped does it feel? I mean, obviously it's small, but does the zero-g environment make it feel less cramped?

Whitson: Actually, the ISS has six modules, so it doesn’t really feel all that cramped for most day-to-day activities. When we are all together, for example during meals, the space we are in is relatively small. But your question is a good one. In zero-g, it is possible to be above/below someone else and not feel too crowded. I think it would be more challenging to work/live in the equivalent amount of space on the ground.

From: John Dickson, San Bernardino, Calif., Age: 41

Question: I fly low and slow private aircraft. When I look up during a night flight, I sometimes see lights from commercial aircraft at altitude. Do you ever see them from orbit? Thank you, and best wishes from the San Bernardino County Sheriff's Aero Squadron.

Whitson: No, I’ve never seen lights from commercial aircraft, but I have seen satellites passing by … at a distance of course. They look pretty much like they do on the ground, a bright, moving star.

From: Don Biege, Silver Lake, Kan., Age: 50

Question: We view personal hygiene on Earth as a routine task. On board the ISS, it becomes a difficult and time-consuming problem. The question is: How do you do laundry, or do you?

Whitson: We don't do laundry. We wear our clothes for two or three days, then use them to work out in, and after that, we throw them into the Progress cargo vehicle. This vehicle burns up upon re-entry into the Earth's atmosphere, so that is how we dispose of our dirty clothes.

From: Kirby Runyon, Spring Arbor, Mich., Age: 17

Question: This question is for Peggy Whitson. With such an apparently strong interest in biology and chemistry, what motivation did you have for becoming an astronaut? Was it because of a love for space or some other factor?

Whitson: I was interested in becoming an astronaut from an early age. I was inspired by seeing the astronauts walk on the Moon, and when I graduated from high school, they selected the first female astronauts. At that point in time, it became my goal to become an astronaut.

From: Hayden Campbell, Cary, N.C., Age: 9

Question: What experiments aboard the space station are the most closely linked to your education? Do you have to provide a muscle biopsy for an experiment?

Whitson: The liver cell experiment and the study of renal stone risk in astronauts are the experiments most closely related to my background. In fact, I'm the principal investigator for the renal stone risk study. There is a pre- and post-flight experiment for which we are providing muscle biopsies.

From: Mary Gow, Warren, Vt., Age: 48

Question: Is the "Speed Limit 17,500" sign still posted in the Unity Module or anywhere else on the space station? Thank you.

Whitson: Yes, the speed limit sign is still posted in Unity.

From: Joanna Deaton, Memphis, Tenn., Age: 6

Question: How long does it take for the experimental crystals to grow?

Whitson: The length of time for the crystals to grow is dependent on what type of crystal is being formed. One advantage of the station is that we can grow crystals for long periods (months) to try and get the maximum size/quality.