The space probe Voyager 1 may soon have company in interstellar space.
Voyager 2 has detected an increase in cosmic rays that originate outside our solar system, NASA announced. That could indicate the probe, which was launched 41 years ago, is nearing the edge of the heliosphere, a giant bubble that surrounds the sun and the planets.
When Voyager 2 leaves the solar system, it will become the second human-made object to enter interstellar space, NASA said.
Its twin probe, Voyager 1, got there first in 2012 after detecting a similar increase in cosmic rays. Voyager 2 is almost 11 billion miles from earth.
Both it and Voyager 1 were launched in 1977. Their primary mission was to explore Jupiter and Saturn.
In case the probes ever encountered alien life, each of them carried a gold-plated record containing sights and sounds from earth, including the song “Johnny B. Goode,” written and performed by Chuck Berry.
Lasting longer than ever expected, Voyager 2 continued through the solar system to Uranus and Neptune.
Voyager 1’s path took it away from the planets toward interstellar space.