Determination of armor thickness necessary for meteoroid protection.

Simulated space environment performance tests of Apollo lunar module in thermal vacuum environment.

A statistical analysis was performed with use of Smithsonian Astrophysical Observatory's data on photographic meteors with use of weighting factors developed at Lewis Research Center for correction of various biases involved in meteor photography. The analysis used an armor damage criterion supplied by Ames Research Center. Although the analysis was restricted to Earth's orbit about Sun, implications are discussed regarding total population of meteoroids throughout the solar system. In Earth's orbit about the Sun, advantage was found for cylindrical armor extending in the solar direction and a plane sheet alined normal to apex of Earth movement.