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Which of these NASA missions was launched in 1977? Skylab, Galileo, Voyager or Viking? Two unmanned spacecrafts were launched as part of the Voyager missions in 1977.
And both of them are still out there, farther away from the Earth than Pluto, still gathering info about the universe more than 40 years after they launched. The cost of the mission when converted to today's dollars is roughly $2 billion.
And it's not just sending data back. The two spacecraft are also carrying info about Earth. Gold plated copper discs with instructions on how to play them are also onboard Voyager in case they're picked up by anything that wants to know about human life. Researchers say that's very unlikely.
They compare the discs to a tiny message in a bottle thrown into the greatest expanse of oceans. But they include greetings in 55 languages, music, natural and manmade sounds. They also have pictures —— snapshots of human life in the 1970s including this one from the 1972 Olympics, a depiction of human sport through a footrace.
