ABSTRACT
The hypothesis that the moon could harbor viable life forms was not verified on analysis of the first samnples from the Apollo 11 mission. Biological examnination of 50 grainis of the butlk fines confirmn the negative results obtained by the Manned Spacecraft Center quarantine teamyz. No viable life forms, including terrestrial contaminants, were found when the sample was tested in 300 separate environmtenits. Only colored illorganiic artifacts, resembling mnicrobial clonies, appeared aroun1cd some particles. Manned Spacecraft Center, Houston.
Subject(s)
Extraterrestrial Environment , Microbiology , Astronomical Phenomena , AstronomyABSTRACT
Although many experiments have been suggested and described for the detection of biological activity in planetary exploration, each experiment has required its own sample for the detection of a specific phenomenon. An experimental design which could detect growth, catabolic and anabolic activity on a single sample is described. Growth is monitored in a liquid medium which is in contact with, and chemically influenced by, a relatively large sample. Catabolic activity is indicated by changes in the gas composition of the atmosphere above the sample. Anabolic activity is indicated by the appearance of reduced carbon compounds, from oxidized precursors, in the liquid medium.
Subject(s)
Exobiology/methods , Extraterrestrial Environment , Space Flight/instrumentation , Carbon Dioxide/analysis , Carbon Dioxide/metabolism , Culture Media , Methane/analysis , Methane/metabolism , Organic Chemicals , Soil/analysisABSTRACT
The optical density of suspensions of microorganisms was measured at two different positions in a spectrophotometer cuvette compartment. From these two measurements, the particle size and the particle concentration could be estimated. Estimates of particle numbers were not significantly different from those obtained by direct microscopic counting.
Subject(s)
Biometry , Microbiology , Optics and Photonics , Bacteria , Eukaryota , Fungi , SpectrophotometryABSTRACT
In the search for life on other planets, experiments designed to detect the growth of microorganisms may prove to be definitive when coupled with chemical characterization and metabolic experiments. If organisms are not abundant, growth provides the only means for obtaining a large mass of biological material suitable for chemical compositional analyses and metabolic assays. Several methods of monitoring growth are described. Of these, optical monitoring in a unique system free of soil particles is advanced as the most appropriate. Theoretical problems related to the formulation of culture media are discussed, and several possible solutions are proposed. The sampling system, the type of monitoring, the size and placement of inoculum, and the medium volume and composition are contingent upon one another and must be integrated without sacrifice to the biological demands.
