The moon always has been an object of fascination for mankind, but once President John F. Kennedy pledged in 1961 that the U.S. would send a manned spacecraft there within a decade, one of the first questions was entirely practical: Where would they land? An extraordinary map, the USAF Lunar Wall Mosaic, produced the year after Kennedy's speech, helped provide the answer. The 1969 Apollo 11 mission landed safely in an area called the Mare Tranquillitatis (Sea of Tranquility). Today, a copy of the map is preserved at the Library as one of the most important -- and practical -- maps in human history.