NASA's Voyager 1 reaches the 'gateway to the galaxy'

Despite traveling 36 years and 11 billion miles (18 billion kilometers) from home, the intrepid Voyager 1 spacecraft still has not left the solar neighborhood. But all indications are that it is now crossing a major threshold to the rest of the galaxy. (Related: “Voyager at the Edge: Cosmic Roadtrip Hits Milestone.” )

New research published this week in the journal Science offers tantalizing clues about Voyager’s current location at the edge of the solar system, or heliosphere—the bubble-like boundary that divides the realm of the sun’s influence from interstellar space.

The specific region Voyager is currently sailing through has been dubbed the “magnetic highway.” It’s located within the outermost part of the heliosphere’s border, called the heliosheath. A confusing place, this highway is where there appears to be a connection between the solar and interstellar magnetic lines, and is where the flow of charged particles moves in and out of the solar system.

Newly released Voyager data from August 2012 indicate it’s instruments had detected the solar wind—the particles emanating from the sun—that had been buffeting the spacecraft for nearly four decades practically flat-lined. At the same time, sensors detected skyrocketing levels of incoming galactic particles from outside the solar system. These cosmic rays are thought to originate from the violent explosions given off by dying stars that go supernova.