Pioneers and Voyagers

In the fall of 1958, Pioneer 1 was launched into lunar orbit as a dress rehearsal for the planetary probes that followed. The rest of the Pioneer craft probed the inner solar system for planetary information, and Pioneers 10 (1972) and 11 (1973) explored Jupiter and Saturn, the giants at the far end of our solar system. Later, in 1978, Pioneer Venus 1 and Pioneer Venus 2 orbited Venus to make surveys of that planet’s lower atmosphere and, using radar imaging, penetrated thick gaseous clouds in order to reveal the spectacular and forbidding landscape below.