Voyager discovers ‘magnetic highway’ at edge of solar system

Earlier this year a surge in a key indicator fueled hopes that the craft was nearing the so-called heliopause, which marks the boundary between our solar system and outer space.

But instead of slipping away from the bubble of charged particles the Sun blows around itself, Voyager encountered something completely unexpected.

The craft’s daily radio reports sent back evidence that the Sun’s magnetic field lines was connected to interstellar magnetic fields. Lower-energy charged particles were zooming out and higher-energy particles from outside were streaming in.

They called it a magnetic highway because charged particles outside this region bounced around in all directions, as if trapped on local roads inside the bubble, or heliosphere.