Well they think they know where the XTO's came from. A Red Dwarf about 63LY out. NASA "Cannot understand" how plain old rocks can make corrections or move in such a specific trajectory. "After all, they are only rocks". They said this several times. Just to make certain we all remembered that it is impossible for extra-solar life to come to earth. As one very angry bureaucrat kept saying "THERE ARE NO LITTLE GREEN MEN!!! These are JUST ROCKS!!!!!----In other news. The US Navy admitted that they have known that UFO's have "tailed" there battle fleet for decades. It was only the advent of anti-stealth radar that allowed them to "see" the UFO's on a regular basis.---Ray
To be fair a recent solar storm and it's differing effects on Voyager 2(at the heleopause) and Voyager 1 (slightly beyond the heleopause) just rewrote our understanding of the system's boundary and the effects it has.