Among the exobiological studies that can be carried out uniquely at a lunar 

 base are the direct search for evidence of life forms in interplanetary space 

 (panspermia); determination of the quantity and form of organic and biogenic 

 compounds in lunar soil (in a very-low-organic-background laboratory environ- 

 ment); study of the survivability of terrestrial organisms in the lunar environ- 

 ment; study of the frequency history of cometary impacts on the Moon (and, 

 consequently, Earth); gathering of evidence pertinent to the theory of episodic 

 extinctions on Earth related to cosmic events; and conduct of astronomical 

 investigations of interest to the exobiology community such as those previously 

 mentioned. Also, the search for extraterrestrial intelligence (SETI) may require 

 the radio-quiet lunar far side in order to conduct a sufficiently sensitive search, 

 shielded from terrestrial interference. 



According to current concepts, the initial lunar base will have aspects of the 

 Earth-orbit Space Station from which it will evolve. The early base will have geo- 

 logical and biological laboratory facilities focusing on understanding how to best 

 utilize the lunar materials and environment for scientific investigations and life- 

 support functions. As production capability grows at the lunar base, new facili- 

 ties may become available for research. This includes very large, very high 

 vacuum chambers; very high temperature and very low temperature systems of 

 substantial dimensions; chambers of very low natural magnetic field; very low 

 natural radiation background facilities (buried facilities, with natural-material 

 barriers constructed from uranium-potassium-free lunar materials); facilities 

 nearly totally free of light (organic) elements and free or capable of being iso- 

 lated from human-introduced biogenic compounds; and laboratories free of 

 metallic contaminants found in many terrestrial environments. All of these 

 should be rather easily developed on the Moon and can be made available inex- 

 pensively once the initial base is able to govern its own growth. 



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