Into the unknown

12/11/2012

NASA launched Voyager 1 and its twin, Voyager 2, in 1977. The mission of the space probes: to tour the outer planets and beyond.

Thirty-five years and 11 billion miles later, Voyager 1 has finally reached the edge of the solar system. It is about to enter a region of space that scientists didn’t know existed.

In 2004, Voyager left the region of space dominated by the sun and the planets. It entered the heliosheath, a region where supersonic streams of particles from the sun — so-called solar wind — slow down, but can churn up cosmic turbulence.

Voyager 1 has spent years sailing through the heliosheath, leaving the solar wind and the influence of the sun’s magnetic field behind. The slack has been taken up by elevated amounts of low-energy cosmic rays as it approaches an unknown region of space.

NASA scientists have noticed the strengthening of what they believe 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.

They 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 it enters interstellar space, but it could be months or even years.

It takes 17 hourst to get a signal back from Voyager 1, but it is still transmitting new and useful information. It will do so until 2025, when it will lose power, shut down, and drift through what should be interstellar space.

With luck, our species will have a reunion with Voyagers 1 and 2 once we’re capable of interstellar travel. We can scoop them up during one of the jaunts to and from a nearby star system and place them in a museum.

The technology of today’s typical cell phone is far more sophisticated than the technology on Voyager 1. Yet nothing on this side of the solar system has seen as much as it has.