Twin probe Voyager 1 crossed into the heliopause in 2012, but its Plasma Science Experiment (PLS) instrument – which Voyager 2 will use to gather information – was no longer working.
Launched weeks before Voyager 1 in 1977, Voyager 2 was originally built to last five years and conduct studies of Jupiter and Saturn. The craft has continued to travel however and after 41 years in space, is now NASA's longest-running mission.
Mission operators can communicate with Voyager 2, but information being transmitted from the probe takes more than 16 hours to reach Earth.
"Working on Voyager makes me feel like an explorer, because everything we're seeing is new," John Richardson, principal investigator for the instrument, said in a press release. "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 seeing things that no one has seen before."
"To have the Voyagers sending back information about the edge of the sun's influence gives us an unprecedented glimpse of truly uncharted territory," said Nicola Fox, director of the Heliophysics Division at NASA.
Voyager's science team will also study data collected by three other on-board instruments — the cosmic ray subsystem, the low energy charged particle instrument, and the magnetometer — all built to give a clearer picture of the environment Voyager 2 is traveling through.