Pioneer plaque

from wikipedia:

The Pioneer plaques are a pair of gold anodized aluminum plaques which were placed on board the Pioneer 10 and Pioneer 11 spacecraft, featuring a pictorial message from humanity, in case either Pioneer 10 or 11 are intercepted by extraterrestrial beings. 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 plaque is attached to the antenna support struts in a position that shields it from erosion by stellar dust.

The Voyager Golden Record, a much more complex and detailed message using (then) state-of-the-art media, was attached to the Voyager spacecraft launched in 1977.

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