A committee that existed from 1957 until 1973 whose space panel advised the US president on space exploration advances and priorities. It was created in the 1950s by US president Dwight Eisenhower, and also provided intelligence information on Soviet space capabilities. In 1967, PSAC (pronounced ‘pea-sack’) anticipated the space shuttle by recommending that ‘Studies should be made of more economical ferrying systems, presumably involving partial or total recovery and use.’