When NASA launched Voyager 1 and its twin, Voyager 2, in 1977, Jimmy Carter was in the first year of his presidency and Fleetwood Mac's "Rumours" defined the national mood. "Star Wars" was breaking movie box office records, the World Trade Center was still new, the "Son of Sam" was caught after a year long reign of terror and Elvis Presley and Groucho Marx died within days of each other.
America was still mourning the loss of two of its biggest icons when the space probes quietly lifted off for a tour of the outer planets and beyond. Thirty-five years and 11 billion miles later, Voyager 1 has finally reached the edge of the solar system and is about to enter a region of space scientists previously didn't know existed.
In 2004, Voyager 1 left the region of space dominated by the sun and the planets and entered the heliosheath, a region where supersonic streams of particles from the sun -- "the solar wind" -- slow down, but still are able to churn up cosmic turbulence.
Voyager 1 has spent years sailing through the heliosheath, leaving the solar winds and the influence of the sun's magnetic field behind it. The slack has been taken up by elevated amounts of low-energy cosmic rays as it approaches a previously unknown and unpredicted region of space.
NASA has noticed the strengthening of what it believes to be the magnetic field of interstellar space on Voyager 1 as it passes beyond the heliosheath and beyond the influence of the sun's magnetic field. Scientists don't know how long Voyager 1, which is several months ahead of its twin on the journey, will travel in this new region before entering the final frontier of interstellar space, but it could be days, months or even years.
It takes 17 hours just to get a signal back from Voyager 1, but it is still transmitting new and useful information. It will continue to do so until 2025 when it will finally lose power, shut down and then drift through what should finally be interstellar space.
With luck, our species will have a grand reunion with Voyagers 1 and 2 once we're capable of interstellar travel. We can scoop them up during one of our jaunts to and from a nearby star system and place them in a museum. Though the average cell phone is far more sophisticated than the technology on the Voyagers, nothing on this side of the solar system has seen as much as they have. The Voyagers have truly gone where no man (or woman) have gone before.