J. William Schopf, Ph.D. 

 Chairperson 



Arthur W. Galston, Ph.D. 



Keith L. Cowing 



Staff Associate 



Gravitational Biology 



Gravity, an obvious and major environmental factor on this planet, has played a 

 signal role throughout the history of life on Earth. Space-based research provides 

 the opportunity to alter the influence of gravity by exposing organisms to 

 fractional gravity levels ranging from essentially zero up to 1 gravity (g). This 

 exposure allows investigation of the effects of gravity on numerous aspects of 

 living systems. Although weightlessness can be artificially created for tens of 

 seconds in parabolic airplane flights, a prolonged state of weightlessness (or, more 

 accurately, "microgravity") can be achieved only during space flight. 



The Gravitational Biology Program is managed at NASA Headquarters. Intramural 

 research is conducted at Ames Research Center, Johnson Space Center, and 

 Kennedy Space Center. As with other areas of life sciences research, extramural 

 research is carried out at a number of universities and research institutions. 



The goals of this program, as stated in the 1986-87 NASA Space/Gravitational Biology 

 Accomplishments (NASA TM 89951), are as follows: "to use the unique charac- 

 teristics of the space environment, particularly microgravity, as a tool to advance 

 knowledge in the biological sciences; to understand the role of gravity in the 

 biological processes of both plants and animals; and, to understand how plants 

 and animals are affected by and adapt to the space flight environment, thereby 

 enhancing our capability to use and explore space." 



A number of recent assessments of space science and technology have noted the 

 importance of space life sciences research in general and gravitational biology in 

 particular. The 1987 report of the National Academy of Sciences' (NAS) Committee 

 on Space Biology and Medicine, A Strategy for Space Biology and Medical Science for 

 the 1980s and 1990s, suggested four major scientific goals that should be addressed 

 by a balanced space life sciences research program. Among these is "to 

 understand the role that gravity plays in the biological processes of both plants 

 and animals." The overall program suggested by the NAS committee addresses 

 both basic and applied research combined with an integrated program of ground- 

 and space-based investigations. The committee recognized that inflight centrifuges 

 would be "essential instruments for the future of space biology and medicine" and 

 recommended that "a variable force centrifuge of the largest possible dimensions 



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