Pioneer

The design etched into the gold-anodized plate carried by Pioneer 10 and Pioneer 11, and which might – in millions of years – be found by other intelligent spacefaring beings. The symbols are designed to identify the Solar System, show the position of Earth, the time the spacecraft was launched, and the type of creatures who built it. The man is shown making a gesture of goodwill.

Any of a series of US Solar System space probes launched 1958–78. The probes Pioneer 1–3, all launched in 1958, were intended Moon probes, but the launch of Pioneer 1A and Pioneer 2 failed, and Pioneer 1B and Pioneer 3 failed to reach their target, although they did fly deep enough into space to measure the Van Allen radiation belts. Pioneer 4 began to orbit the Sun after passing the Moon. Pioneer 5 (1960) was the first of a series to study the solar wind between the planets. Pioneer 6 (1965), Pioneer 7 (1966), Pioneer 8 (1967), and Pioneer 9 (1968) went into orbit around the Sun and monitored solar activity. Pioneer 10 (March 1972) was the first probe to reach Jupiter (December 1973) and to leave the Solar System (1983). Pioneer 11 (April 1973) passed Jupiter (December 1974) and was the first probe to reach Saturn (September 1979), before also leaving the Solar System. NASA ceased to operate Pioneer 10 in April 1997, but re-established contact in March 2002, when the probe had reached a distance of 11.9 billion km/7.4 billion mi from the Earth. The last signals from Pioneer 10 were received in January 2003. Pioneer 11 ceased to function in 1995.

Pioneer 10 and 11 carry plaques containing messages from Earth in case they are found by other civilizations among the stars. Pioneer Venus probes were launched May and August 1978. One orbited Venus, and the other dropped three probes onto the surface. The orbiter finally burned up in the atmosphere of Venus in 1992.