Virtually every medical aspect of space flight was covered by Eleanor O'Rangers at the Fourteenth National STS Meeting in Baltimore in her two-hour presentation on 6 March 1999. She began with 1958, the year after the launch of Sputnik, when the Commission on Bioastronautics tried to identify problems which might be faced by humans under the conditions imposed by weightlessness: would they be able to swallow? How could one predict the effects of weightlessness? There was little time for research and practice to develop, O'Rangers pointed out, but enough was learned from early experiments to predict that humans could survive space flight. The first astronauts were, of course, animals -- Laika, the Russian dog, and chimpanzees in U.S. flights. Though the first long-term experiments and observations were those gathered in Skylab (1973-74), the Russian cosmonauts were much more experienced in long flights, especially after the launching of Mir. O'Rangers covers medical aspects of space flight
by Irma S. Jarcho
As O'Rangers pointed out, we now know some of the adaptations to weightlessness -- some trivial, some life-threatening. The heart loses muscle mass and, indeed, there is muscle mass loss and tone loss all over the body. Without exercise the body could lose 20% or more of its weight mass. Imagine the results of such loss in the long trip to Mars. The astronaut could step out on Mars, fall, and break a hip. Some changes occur immediately, some over time. The problem is not only the changes on the trip but the possible consequences of re-entry.
A considerable portion of O'Rangers' presentation was devoted to a study of pharmacology in space. We do not know how medicines work in space, she noted, and are therefore unsure of what dosages to administer. Microgravity appears to stimulate growth of bacteria and protozoa: Escherichia coli and Staphylococcus aureus not only grow faster but appear to be more resistant in space. Killing them in microgravity required four times the usual lethal dose.
Other pharmacology problems reported by O'Rangers included exposure to the greater amount of radiation in interstellar space. She noted that increased shielding would give rise to a weight problem for the space ship. Another problem is that calcium which dissolves out of the bones in space flight appears to settle in the kidneys and may give rise to kidney stones. Can you imagine being halfway to Mars and developing a kidney stone?
Home Spring 99 Full Screen
The TEACHERS CLEARINGHOUSE FOR SCIENCE AND SOCIETY EDUCATION