PRINCIPAL INVESTIGATOR (S ) : R. Facius, D. Hildebrand, G. Hoeltz, G. Horneck, 



M. Schaefer, B. Toth, Horst Buecker, M. Delpoux, 

 S. Fogel, M. Freeling, E. H. Graul , A. R. Kranz, 

 H. Planel, W. Ruether, U. Scheidemann, C. Thomas, 

 C. A. Tobias, T. Yang, 0. C. Allkofer, R. 

 Beaujean, E. V. Benton, W. Enge , H. Francois, W. 

 Heinrich, C. Jacquot, R. Kaiser, J. P. Massue, E. 

 Obst, D. D. Peterson, R. Pfohl, G. Portal, G. 

 Reitz, E. Schopper, J. U. Schott, and G. Siegmon 



EXPERIMENT TITLE/NUMBER : BIOSTACK III 



PROGRAM/MISSION : Apollo-Soyuz Test Project 



CLASSIFICATION : Microorganism - Spores ( Bacillus subtilis ) 



DISCIPLINE(S) : Cell biology, Radiobiology , Genetics 



OBJECTIVES : To study HZE particle radiation on spore outgrowth, cell 

 development, colony formation, and mutation induction. 



PROTOCOL : The BIOSTACK flight experiment was stored in the R-1 compartment in 

 the Apollo capsule where there was the least shielding from ambient radiation. 

 The specimens were arranged in monolayers and imbedded in polyvinyl alcohol, 

 and stacked between track detector sheets so particle tracks could be 

 located in relation to biological objects and the physical quantities of these 

 particles could be determined. 



EQUIPMENT : There were 2 cylindrical aluminum containers which enclosed a 

 stack of biological specimens and dosimeters. 



RESULTS : Growth was significantly reduced in spores of < 4 m. This 

 result is surprising, but important because dosimetric calculations for the 



-electrons predicted 0.5 m for this reduced survival. Further 

 deviations from normal development were also observed, such as swelling of the 

 first vegetative cell, which did not divide. 



CONCLUSIONS : HZE-particle-induced damage might become manifest if 

 nonreplaceable cells are destroyed. In manned space flight, the primary 

 concern would be the nervous system. However, the risk to man from HZE 

 particles during space flight can be sufficiently lowered if the maximum 

 possible shielding against HZE particle bombardment is ensured in the design 

 and construction of future space vehicles. 



PUBLICATIONS : 116, 121, 122, 124, 188, 472 



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