A specially trained team conducted the postflight dissections. Ames Research Center involvement in the biospecimen sharing program included oversight of the laboratory facilities used by visiting Russian investigators, receipt of flight tissue samples, and coordination of shipment of samples to Russia and France.
A Delayed Flight Profile Test (DFPT) was conducted, beginning with the receipt of rats on June 6, 1991, at Kennedy Space Center using flight RAHF and flight AEM hardware. The DFPT simulated the SLS-1 mission timeline, the flight environmental conditions, including temperature, humidity, and light/dark cycles, and significant operational events, such as hardware maintenance and rodent handling. Noise, vibration, and acceleration profiles experienced during space flight were not simulated.
Both hardware tests verified the utility and functionality of the GPWS and the SMMI. The PCDT using the GPWS and the RAHF was successful. Postflight analysis of the screens collected revealed that particulate accumulation occurred during only one condition and on one screen at less than 50 microns in size. This particulate accumulation was due to the failure of the crew to adequately clean the interior backside of the GPWS front window, which led to the entrapment of material when the window was raised. Proper cleaning prevented a repeat condition during the second particulate release. The SMMI performance exceeded expectations and produced accurate measurements during all trials.
Compared to the ground control rats, flight rats, upon landing, appeared be lethargic, to have reduced muscle tone, and to use their tails less as balancing aids. These effects were more noticeable in the rats housed in the AEMs than in those housed in the RAHF. Flight rats gained less weight during the flight period than did ground controls. There was no difference in body weight gain between rats housed in the RAHF and those housed in the AEM.
The hematology experiments showed that on the day of landing, the flight rats had fewer red and white blood cells than did ground controls, but their levels returned to normal by the ninth day postflight. Muscle studies indicated that functional and structural changes occurring in muscle tissue could impair the normal movement patterns involved in antigravity function and postural control. Housing type was found to affect some of the changes occurring in bone during space flight: singly housed animals were affected to a greater degree and showed slower recovery than group-housed animals. Research on gravity sensors indicated that rats were able to adapt to the microgravity environment better than anticipated. Results also indicated that metabolism, immune cell function, cell division, and cell attachment may be affected by microgravity.
Jellyfish ephyrae that developed in microgravity were normal in most respects, although they showed hormonal changes while in space and abnormalities in swimming behavior after returning to Earth. Ephyrae that were flown after developing on Earth tended to show changes in their gravity-sensing organs. The swimming behavior of both ephyrae hatched on Earth and those that developed in microgravity showed that they had difficulty orienting themselves in space.
Dalton, B.P., G. Jahns, J. Meylor, N. Hawes, T. N. Fast, and G. Zarow. Spacelab Life Sciences-1 Final Report.
NASA TM-4706, August 1995.
NASA. STS-40 Press Kit, May 1991. Contained in NASA Space Shuttle Launches Web site: http://www.ksc.nasa.gov/shuttle/missions/missions.html