Voyager 1 already had the distinction of being the man-made object that has travelled further from Earth than anything else we, as a species, have ever flung out into space, but that isn’t going to stop it from travelling deeper and deeper into the unknown. NASA confirms that the probe is indeed now travelling through interstellar space.
Back in August of 2012, Voyager made international headlines when it was announced that it had actually left the heliosphere. This is essentially a giant bubble of magnetic fields and charged particles that surround our sun and extends far past Pluto. Plasma from the sun, so-called solar wind, pushes against the pressure of the interstellar medium, which is the hydrogen and helium mixture that makes up much of our galaxy. Interstellar space begins where the heliosphere ends.