Pioneer 11 (also known as Pioneer G) is a 259-kilogram (569 lb) roboticspace probe launched by NASA on April 6, 1973 to study the asteroid belt, the environment around Jupiter and Saturn, solar wind, cosmic rays, and eventually the far reaches of the solar system and heliosphere.It was the first probe to encounter Saturn and the second to fly through the asteroid belt and by Jupiter. Due to power constraints and the vast distance of the probe, communication has been lost since November 30, 1995.
Pioneer 10 and Pioneer 11 carry a gold-anodized aluminum plaque in the event that either spacecraft is ever found by intelligent life-forms from other planetary systems. The plaques feature 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.
