When signals from Pioneer 10 can no longer be heard here on Earth, it will start another, perhaps more important mission as it continues its journey into interstellar space. Pioneer 10 will become the cosmic equivalent to a message in a bottle cast into the sea.
It was launched on March 2, 1972, from Cape Canaveral, Florida. Between July 15, 1972, and February 15, 1973, it became the first spacecraft to traverse the asteroid belt. Radio communications were lost with Pioneer 10 on January 23, 2003, because of the loss of electric power for its radio transmitter.
On-board Pioneer 10 is a special message from mankind to whoever may find it. Attached to the antenna support struts of the spacecraft in a position where it would be shielded from erosion by interstellar dust is a gold- anodized aluminum plate.
On the Plate are the figures of a man and a woman next to a line silhouette of the spacecraft. The bottom of the plaque shows schematically the path that Pioneers 10 took to escape the solar system – starting at the third planet from the Sun accelerating with a gravity assist from Jupiter out of the solar system. Also shown to help identify the origin of the spacecraft is a pattern etched on the plaque that represents the position of our Sun relative to 14 nearby pulsars and a line directed to the center of our Galaxy.
When Pioneer 10 flew by Jupiter, the spacecraft acquired sufficient kinetic energy to carry it completely out of our Solar System. In about 100,000 years, it will have flown to the next nearest star. There it could pass through a planetary system who may have evolved intelligent life. If that life possesses the ability, the message from Earth may be found and deciphered.