Analogs for Planetary Exploration
Planning and implementation of astronaut observations and photography from lunar orbit during the Apollo program were based on two expectations: (1) orbiting astronauts would be able to add to our knowledge by describing lunar features from their unique vantage point, and, (2) as illustrated by the Gemini Earth-orbital missions, expertly obtained photographs would allow us to place detailed information from field exploration into a regional context. To achieve these goals, the astronauts had to be thoroughly familiar with concepts of lunar geology and intellectually prepared to note and document the unexpected. This required mission-specific training to add to their store of knowledge about the Moon. Because the activity was not part of the original program objectives, the training was conducted at the behest of the astronauts. The training time grew from occasional briefings on the early flights to extensive classroom sessions and flyover exercises for a formal “experiment” on the last three missions. This chapter summarizes the historical development and salient results of training the Moon-bound astronauts for these tasks. The astronaut-derived orbital observations and photographs increased our knowledge of the Moon beyond that possible from robotic sensors. Outstanding results include: realization of the limitations of photographic film to depict natural lunar surface colors; description and documentation of unknown features on the lunar farside; observation by Apollo 15 of dark-haloed craters that helped in the selection of the Apollo 17 landing site; and real-time confirmation that the “orange soil” discovered at the Apollo 17 site occurs elsewhere on the Moon.