Voyager Program

NASA launched Voyager 1 and Voyager 2 in August and September 1977, timed to take advantage of a rare planetary alignment that occurs once every 176 years. The alignment allowed a gravity-assist trajectory past Jupiter, Saturn, Uranus, and Neptune. Both spacecraft performed the grand tour. Voyager 2 remains the only spacecraft to have visited Uranus and Neptune. It found active geysers on Triton. Voyager 1 took the Family Portrait in 1990 — a mosaic of the solar system from 6 billion kilometers out. Earth appears as a pale blue dot 0.12 pixels wide. Carl Sagan wrote: Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves. Voyager 1 crossed the heliopause — the boundary of the solar wind, the technical edge of the solar system — in 2012. It is now in interstellar space. Both spacecraft are still transmitting. The signal from Voyager 1 takes 22 hours to reach Earth at the speed of light. They carry gold-plated copper records with greetings, music, and images — assembled under Carl Sagan's direction — in case they are ever found.