Nearly 36 years after its launch, NASA's Voyager 1 spacecraft is nearing the edge of the solar system and interstellar space.
NASA reported today that its getting data from the spacecraft that indicates it's now more than 11 billion miles from the sun.
At this pace, Voyager 1, launched on Sep. 5, 1977 to study the outer Solar System and interstellar space, should soon be the first human-made object to leave the solar system.
Voyager 1 is believed to be near the edge of the heliosphere, which is akin to a bubble around the sun. NASA reported that the spacecraft is so close to the edge of the solar system that it now is sending back more information about charged particles from outside the solar system and less from those inside it.
"This strange, last region before interstellar space is coming into focus, thanks to Voyager 1, humankind's most distant scout," said Ed Stone, Voyager's project scientist at the California Institute of Technology, in a statement.
"If you looked at the cosmic ray and energetic particle data in isolation, you might think Voyager had reached interstellar space, but the team feels Voyager 1 has not yet gotten there because we are still within the domain of the sun's magnetic field." he added.
NASA noted that its scientists don't know exactly how far Voyager 1 needs to travel to enter interstellar space. It could take a few months or even years. The bubble around the solar system extends at least 8 billion miles past the furthest planet from the sun.
Scientists are eager to see what Voyager 1 will find in interstellar space, which is believed to be filled with matter from stars.
Part of Voyager 1's mission is to measure the size of the heliosphere.
Voyager 1 launched with its twin spacecraft, Voyager 2. Both have flown past Jupiter, Saturn, Uranus and Neptune. In 1990, they embarked on a mission to enter the interstellar region.
Voyager 2 is currently just 9 billion miles away from the sun, NASA said.
