Nasa's long-running Voyager 1 spacecraft has entered a new region at the edge of the solar system and is close to exiting it forever.
Scientists have dubbed this region the "magnetic highway" and it's the last stop before interstellar space, or the space between stars.
The findings were presented Monday at a meeting of the American Geophysical Union meeting in San Francisco.
Voyager 1 and its twin Voyager 2 launched 35 years ago on a tour of the outer planets.
Afterward, both spacecraft continued to hurtle toward the fringes of the solar system.
Mission chief scientist Ed Stone said it's unknown when Voyager 1 will finally break through to interstellar space.
Once that happens, it'll be the first manmade object to leave the solar system.
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