PRINCIPAL INVESTIGATOR(S ): G. Horneck, Horst Buecker, R. Kaiser, J. P. 



Massue, R. Pfohl, W. Enge , 0. C. Allkofer, K. 

 Bartholomae, R. Beaujean, W. Heinrich, K. Fukui, 

 Eugene V. Benton, E. Schopper, G. Henig, J. U. 

 Schott, H. Francois, and G. Portal 



EXPERIMENT TITLE/NUMBER : BIOSTACK I, II 



PROGRAM/MISSION : Apollo' 16, 17 



CLASSIFICATION : Microorganism - Spores ( Bacillus subtilis) 



DISCIPLINE(S) : Radiobiology , Genetics, Cell biology 



OBJECTIVES : To study the biological effects of individual heavy nuclei with 

 high energy loss (HZE), to obtain as much information as possible on the 

 mechanisms of biological damage by HZE particles, to measure the charge and 

 energy spectra of cosmic radiation within the Apollo Command Module, and to 

 provide data to allow an estimate of the hazard to man from space radiation. 



PROTOCOL : Bacterial spores, protozoan cysts, plant seeds, shrimp eggs and 

 insect eggs were studied using several physical radiation detectors. The 

 BIOSTACK unit was flown in the Command Module where shielding to ambient 

 cosmic radiation was minimal. After flight, the ground controls and the 

 flight package were disassembled and the particle hits were graphed. 



EQUIPMENT : Hermetically sealed aluminum container, containing a series of 

 select biologic material, each sandwiched between several types of dosimeters 

 (nuclear emulsions, cellulose nitrate, polycarbonate, LiF), and thermistors. 



RESULTS : The germinating fraction of the spores hit was more than 90% in the 

 BIOSTACK I experiment and reached nearly 100$ in the BIOSTACK II experiment. 

 This fraction did not differ significantly from that of the controls, 

 indicating a high resistance to HZE-particle bombardment. Pseudogermination 

 was not observed on the spore hits. 



CONCLUSIONS : The Bacillus subtilis spores were not influenced by the unusual 

 environmental parameters and factors of spaceflight. 



PUBLICATIONS : 113, 114, 115, 116, 117, 118, 119, 120, 125, 126, 1bb, 213, 2b3 



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