The Pioneer plaques are a pair of gold-anodized aluminium plaques which were placed on board the 1972 Pioneer 10 and 1973 Pioneer 11 spacecraft, featuring a pictorial message, in case either Pioneer 10 or 11 is intercepted by extraterrestrial life. The plaques show the nude figures of a human male and female along with several symbols that are designed to provide information about the origin of the spacecraft.
The Pioneer spacecraft were the first human-built objects to leave the Solar System. The plaques were attached to the spacecraft’s antenna support struts in a position that would shield them from erosion by stellar dust.
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