David S. McKay, American biochemist and geologist (born 1936)

David Stewart McKay was the chief scientist for Astrobiology at the Johnson Space Center. During the Apollo program, McKay provided geology training to the first men to walk on the Moon in the late 1960s. McKay was the first author of a scientific paper postulating past life on Mars based on evidence in Martian meteorite ALH 84001, which had been found in Antarctica. Despite there being no convincing evidence of Martian life, the initial paper caused enormous scientific and public attention. The NASA Astrobiology Institute was founded partially due to community interest in this paper and related topics. He was a native of Titusville, Pennsylvania.