re: Will Pioneer 10 ever reach Aldebaran?
Maybe it has something to do with where we presently are in our Local Bubble (http://www.habitablezone.com/nexus/index.asp?svcpt=space)... coupled by hydromagnetic/magnetic waves (Alven waves: http://adsabs.harvard.edu/abs/1990PhDT........19L). The last link may not be the best, but you'll get the idea.
Granted that there must be 'static' waves/energy created between stars and that may bring our Pioneer down to a halt. Unless he was equipped with thrusters (so that another star's magnetic field such as Aldebaran would take over), but I highly doubt that it was.
Love hearing about our Pioneers. Thanks!
Best.