The Voyager spacecrafts were launched in August and September of 1977. Since then, the two probes have taken different paths. Though Voyager 2 was launched first (August 20), Voyager 1 (September 5) zoomed past Saturn and Jupiter. And, in 2012 Voyager 1 became the first human-made object to leave our solar system and enter interstellar space. Now, according to NASA and space.com, it looks like Voyager 2 will soon follow.
In late August of this year, NASA started recieving data from Voyager 2 indicating an “uptick” in the amount of cosmic rays hitting the spacecraft. That data matched closely with what was happening with Voyager 1 as it made its way out of our celestial neighborhood.
Voyager 2 is currently somewhere around 11 billion miles from Earth. So, you know, far. As the probe gets closer to the edge of the heliosphere (the protective bubble of solar wind provided by our sun) more and more cosmic rays (super-fast particles hurtling through space) hit it. But, because Voyager 1 and 2 have taken different paths through the solar system, scientists can’t tell how close Voyager 2 is to the heliopause (very edge of the solar system) until it’s crossed the threshold. Once it does, cosmic rays will bombard it. Then it will be clear.
Voyager Project Scientist Ed Stone said, “”We’re seeing a change in the environment around Voyager 2, there’s no doubt about that,” and, “We’re going to learn a lot in the coming months, but we still don’t know when we’ll reach the heliopause. We’re not there yet — that’s one thing I can say with confidence.”
So, say your goodbyes. It could happen in a month or three. But, soon, Voyager 2 will leave us and cross into the great unknown.