Arthur C Clarke with Leonov, Vienna, 1968. Arthur Charles Clarke (b 1917) became a leading science fiction writer following a period of work in scientific research. Alexei Arkhipovich Leonov (b 1934), a Rusian astronaut, was the first human to walk in space. In 1975 he took part in the joint US-UsR Apollo-Soyuz space mision. Here, the two men laugh over a list of instructions for the use of a zero gravity toilet. Photograph by Schikola of Vienna.
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