The Long Run

Schematic of Voyager spacecraft.

Hurtling through space for more than 35 years, Voyager 1 still hasn't left our solar system. But scientists think it is getting close.

The sturdy spacecraft started to taste interstellar space at a distance of about 11 billion miles (18 billion kilometers) from the sun. Scientists think it is crossing the final boundary of our solar system, but they don't yet know when it will reach true interstellar space.

"Although Voyager 1 still is inside the sun's environment, we now can taste what it's like on the outside because the particles are zipping in and out on this magnetic highway," said Edward Stone, Voyager project scientist.

"We believe this is the last leg of our journey to interstellar space. Our best guess is it's likely just a few months to a couple years away. The new region isn't what we expected, but we've come to expect the unexpected from Voyager."

Voyager Interstellar Mission Profile