February 1, 2002

Friday, February 1, 2002. Some tough questions required some thoughtful and detailed answers Friday from astronaut Dan Bursch, KD5PNU. Bursch represented the International Space Station's Expedition Four crew during an interview with seven high school physics students at Butte High School in Butte, Montana. The Q and A session was the crew's second school contact arranged by ARISS, a joint effort of AMSAT, ARRL and NASA.

Student Oliver Huang asked a two-pronged question, wanting to know whether chemical reactions that normally precipitate on Earth also do the same in microgravity, and whether bones heal the same in microgravity as on Earth. Bursch took the time to answer the question properly, explaining that on board the ISS some chemical reactions work differently because the densities of various compounds cause the compunds to mix in unexpected ways. As for the question about bones, Bursch said that he didn't know for sure, but that his best guess was that bones heal differently in microgravity, and that the stress of gravity led to quicker healing for fractured bones. Bursch speculated that if one of the crew should suffer a fracture, the doctors on the ground would prescribe some sort of stress on the bone to aid healing.

Lori Stenson asked,"How long does your oxygen supply last during an EVA?" Bursch answered, "It depends on the suit," but went on to explain that even though the crew's spacesuits have eleven hours worth of oxygen, the real limiting factor was the suit's lithium hydroxide, which is capable of scrubbing carbon dioxide from the air for only nine hours.

About 90 science students were present for the interview, and 30 of them were ready to ask questions. Reporters from the local newspaper and television station were on hand, and two local radio stations, KBOW and KRBM, broadcast the interview live. MSNBC also carried the event live on its website. Coordinating teacher Sandy Shutey exclaimed afterwards,"This was absolutely fantastic! It's one of the best things we've ever done!" She went on to explain that the event was a hands-on culmination of her students' several-months' study of space topics.

Bursch and his crewmates Yuri Onufrienko, RK3DUO, and Carl Walz, KC5TIE, passed over Australia during the telebridged session. Radio contact with Tony Hutchison, VK5ZAI, in Paringa, was relayed by Worldcom, Inc., to Butte. Roy Neal, K6DUE, moderated the event, and ARISS mentor Tim Bosma, W6ISS, helped the students prepare for the contact.