Back in July we reported on a new theory explaining why both Pioneers 10 and 11 were decelerating at a rate that seemed to defy Newtonian physics. The answer, it seemed, had to do with heat from the electrical subsystems and the decay of plutonium which was pushing back on the craft. But now, a researcher from the University of Missouri says this is wrong — and that our unexpected measurements of the Pioneer probes can be explained by taking the ongoing expansion of the universe into account.

read the complete article @ The real reason why the Pioneer spacecrafts appear to be slowing down.