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Creators/Authors contains: "Johnson, Robert E."

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  1. The lunar exosphere is generated by a variety of processes: photodesorption from solar UV radiation (PSD), solar wind ion sputtering, meteoritic bombardment, radioactive decay, and thermal desorption. While remote or orbital temporal measurements provide in situ clues to source mechanisms, individual ejection processes are more easily and deeply investigated in laboratory experiments on returned Apollo samples and analogs, allowing quantitative comparisons at lunar-like pressures and temperature. The importance of laboratory experiments cannot be overemphasized, providing measurements of ejection probabilities relevant to exospheric formation, as well as metrics such as surface charge, surface composition and phase, and meteoritic-impact plume characterization. These parameters can be convolved to describe telescopic observations as well as phenomena observed at the lunar surface by orbital / lander measurements, providing ground truth for models of spatial and temporal variations in the exosphere. The following discussion of laboratory work pertinent to the generation of the lunar atmosphere is a starting point for those interested in laboratory simulations and is by no means an exhaustive review. 
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