PRINCIPAL INVESTIGATOR(S ) : Jesse N. Phillips 



EXPERIMENT TITLE/NUMBER : Experiments with Photo-Synthetic Organisms in 



Discoverer Vehicles 



PROGRAM/MISSION : Discoverer XVII 



CLASSIFICATION : Microorganism - Algae ( Chlorella ellipsoidea ) 



DISCIPLINE(S) : Cell biology 



OBJECTIVES : To help provide rudimentary knowledge of biological responses to 

 space environments. 



PROTOCOL : Two ml of cell suspension from a healthy Chlorella culture were 

 pipetted into glass vials which were heat sealed. Ground controls were also 

 made. Vials were shipped to launch site under refrigeration. Radiation 

 dosimetry was provided inflight. On recovery, density was determined by using 

 a photoelectric colorimeter. Growth rate was also calculated. The samples 

 were also tested for biochemical mutants, morphological abnormalities, and 

 pigment changes. 



EQUIPMENT : Glass vials, chemical dosimeters, modified Kratz's medium (D-17), 

 Evelyn photoelectric colorimeter, alanine, albumin, silver-activated phosphate 

 glass rods, Ansco 522 film, neutron sensitive film, antimony foil, nuclear 

 track plates . 



RESULTS : Laboratory and flight samples responded in identical fashion. Both 

 samples showed the same auxotrophic mutants. There were no anomalies in 

 growth, pattern of growth, shade of color or uniformity of pigment. There 

 were no anomalies in pigment or morphology in the samples observed. Cell 

 counts on flight samples, ground controls and laboratory controls corresponded 

 closely. 



CONCLUSIONS : These photosynthetic organisms are capable of living and 

 retaining viability in a space environment. None of a number of physiological 

 responses evaluated had been detectably harmed by exposure to space 

 environment. It appears the algae, Chlorella ellipsoidea could survive and 

 function as a part of a life support system when exposed to radiation levels 

 for the orbital time period of Discoverer XVII satellite. 



PUBLICATIONS : M22, 425 



166 



