According to Mother Nature Network, Voyager 2 has reached interstellar space.
The deep space probe launched 41 years ago, making it NASA's second-longest mission to date.
The first Voyager probe entered interstellar space about six years ago.
But Voyager 2 is equipped with an instrument that the maiden craft lacked.
Known as the Plasma Science Experiment, the Voyager 2 has a sensor for detecting the speed of solar wind particles emitted by the Sun.
