PRINCIPAL INVESTIGATOR (S ): Gerald R. Taylor, R. A. Long, and Walter L. Ellis 



EXPERIMENT TITLE/NUMBER : Microbial Response to Space Environment 



PROGRAM/MISSION : Apollo 16 



CLASSIFICATION : Animal - Nematode larvae ( Nematospiroides dubius ) 



DISCIPLINE(S) : Radiobiology, Genetics, Cell biology 



OBJECTIVES : To evaluate the effect of a particular space flight on the 

 survival rate of different species. 



PROTOCOL : Each microbial sample containing 100 to 1 million live cells, was 

 housed in chambers or cuvettes for flight and ground controls. Microbes could 

 be suspended in 50pl of fluid or dried on a carrier, and exposed to vacuum of 

 space or retained at 1 atm. An optical filtering system controlled the total 



radiant ? energy reaching exposedgtest systems from a minimum of 4 x 10 

 ergs/cm to a maximum of 8 x 10 ergs/cm . 



EQUIPMENT : Microbial ecology evaluation device (MEED) containing 798 

 cuvettes, 140 neutral density filters, 28 bandpass filters, 8 recording 

 thermometers, one high-energy multicharged particle dosimeter, 64 potassium 

 ferrioxalate actinometry cuvettes, 44 photographic film cuvettes, and 18 

 thermoluminescent dosimeter cuvettes. 



5 2 

 RESULTS : Solar ultraviolet irradiation at 254 run (2 x 10 ergs/cm ) inhibited 



growth to mature worms, and postf light infection of murine host. 



Nonirradiated larvae showed no change in survival rate, infectivity, 



development to adults or their egg production. The egg viability was 



significantly decreased. 



CONCLUSIONS : No statistically valid differences could be detected in the 

 survival of flight samples when compared to corresponding ground-based 

 controls. 



PUBLICATIONS : 354, 503, 504, 505, 513, 514, 515 



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