An awe-inspiring milestone to close out the year. NASA has confirmed that Voyager 2 has officially crossed the heliopause—the protective bubble of particles and magnetic fields created by the Sun—and entered interstellar space.



Launched in 1977, Voyager 2 is now the second human-made object in history (following its twin, Voyager 1) to leave our solar neighbourhood behind. It is currently over 11 billion miles from Earth, yet it is still communicating with us, sending back unprecedented data about the boundary where our Sun's influence ends and the vast, cold medium of interstellar space begins. A phenomenal achievement for a spacecraft built over forty years ago.