The plasma wave science team reviewed its data and found an earlier, fainter set of oscillations in October and November 2012. Through extrapolation of measured plasma densities from both events, the team determined Voyager 1 first entered interstellar space in August 2012.
MORE: http://www.sciencedaily.com/releases/2013/09/130912135507.htm
See also...
The Inside of the Milky Way Galaxy in 3-D
http://www.sciencedaily.com/releases/2013/09/130912092720.htm
Hubble Bubble May Explain Different Measurements of Expansion Rate of the Universe
http://www.sciencedaily.com/releases/2013/09/130909092520.htm
