NASA’s Voyager 2 has become the second human-made spacecraft in history to reach interstellar space. The probe has now exited the heliosphere, that is, the protective bubble of particles and magnetic fields created by the sun.
NASA’s scientists have determined that Voyager 2 crossed the outer edge of the heliosphere on November 5. This outer edge is known as the heliopause.
The heliopause is where the tenuous, hot solar wind meets the cold, dense interstellar medium. NASA’s Voyager 1 crossed this boundary in 2012. Voyager 2 carries a working instrument that will provide first-of-its-kind observations of the nature of this gateway into interstellar space.
Voyager 2 is now 11 billion miles from Earth, from where it will collect ground-breaking data. 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 PLS (Plasma Science Experiment) instrument and a principal research scientist at the Massachusetts Institute of Technology in Cambridge, said in a statement.
“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.”