i thought that the edge of the solar system was at 50,000 au?
"On September 12, 2013, NASA announced that Voyager 1 had exited the heliosphere on August 25, 2012, when it measured a sudden increase in plasma density of about forty times.[3] Because the heliopause marks one boundary between the Sun's solar wind and the rest of the galaxy, a spacecraft such as Voyager 1 which has departed the heliosphere can be said to have reached interstellar space."
source:
http://en.wikipedia.org/wiki/Heliosphere