The Voyager 2 probe has left the Solar System, Nasa has confirmed, becoming only the second man-made object to ever enter interstellar space.

The spacecraft left Earth in 1977, 16 days before its twin Voyager 1, but the later probe ended up travelling faster after gaining a gravity boost at Jupiter and Saturn and so exited the vast plasma bubble created by the Sun - known as the heliosphere - in 2012.

However, unlike its sister craft, Voyager 2 carries a working instrument called the Plasma Science Experiment (PLS) which will provide first-of-its-kind observations as it moves into the space between stars.

“Working on Voyager makes me feel like an explorer, because everything we’re seeing is new,” said John Richardson, principal investigator for the PLS instrument and a principal research scientist of MIT, in Cambridge, US.

“Even though Voyager 1 crossed the heliopause in 2012, it did so at a different place and a different time, and without the PLS data. So we’re still seeing things that no one has seen before.”

The probe also has three other working instruments on board, the cosmic ray subsystem, the low energy charged particle instrument and the magnetometer, which can be used to get a picture of the environment that Voyager 2 is travelling through.