It was on this day in 1977 that Voyager 2 was launched by NASA to explore the planets of our solar system and to take the first up-close photographs of the giant planets Jupiter, Saturn, Uranus, and Neptune.
Just before the Voyagers took off, a committee of scientists, led by Carl Sagan, decided to put on board each Voyager a message from Earth in case extraterrestrials ever found them. At the time, the Cold War was at its height, and some members of the committee considered that these spacecraft and their contents might be the last traces of the human race left in the universe after a nuclear war. The Voyagers were each equipped with a gold-plated phonograph containing a variety of earthly sounds, including a heartbeat, a mother’s kiss, wind, rain, surf, a chimpanzee, footsteps, laughter, the music of Bach and Mozart, and the Chuck Berry song “Johnny Be Good.” Carl Sagan said, “The launching of this bottle into the cosmic ocean says something very hopeful about life on this planet.”
Today, the Voyagers have traveled farther from Earth than any other human-made objects in history. Both have gone well beyond Pluto. Voyager 2 is not headed toward any particular star, although in roughly 40,000 years it should pass 1.7 light-years (9.7 trillion miles) from the star Ross 248. And if left alone for 296,000 years, Voyager 2 should pass by the star Sirius at a distance of 1.32 parsecs (4.3 ly, 25 trillion miles). Voyager 2 is expected to keep transmitting weak radio messages until at least 2025, over 48 years after it was launched.
- This date in science: NASA launched Voyager 2 space probe (astronaut.com)
- Voyager probe did leave solar system, new study says (cbc.ca)