11.12.2013 - By Sarah Castor-Perry, The Naked Scientists
Launched in 1977 to study the Solar system's gas giant planets, Voyager 1 is still operating. But now it's so far away that the Solar wind has weakened and a deluge of cosmic particles from intergalactic space is assailing it. Now interstellar space awaits. But where does the Solar system end and this new frontier begin?