“VOYAGER 1 has entered the final lap of the race to interstellar space,” exults Edward Stone. And this time he is sure that the spacecraft he helped launch nearly 30 years ago has finally reached the very fringes of our solar system.
Voyager 1 was supposed to have reached this milestone nearly three years ago but the evidence was inconclusive. Now it has officially crossed the “termination shock”, the region where the speed of the solar wind drops abruptly from supersonic to subsonic, and has entered the shell of dense solar wind called the heliosheath that separates our solar system…
