A better title would be "number of times NASA has described a fascinating new discovery made with Voyager I as 'leaving the solar system'." The issue is with th

A better title would be "number of times NASA has described a fascinating new discovery made with Voyager I as 'leaving the solar system'." The issue is with the headline writers who avoid words like "heliopause", "heliosphere", and "interstellar plasma". But every one of those hash marks still indicates a region of space that humanity has explored for the very first time.