Space probe vehicle Pioneer 10 crossed the orbit of Neptune and became the first fabricated object to leave the solar system. Pioneer 10 is moving in a straight line away from the sun at a constant velocity of about 12 km/sec. Thirty years after its launch, NASA made successful contact with telemetry received from the probe. It sent information from the one scientific instrument that was still working: the Geiger tube telescope. Onboard the Pioneer 10 is a plaque with a picture that shows the location of our solar system - just in case its ever found.