Just ran across this really interesting article on space.com by Charles Q. Choi, NASA Baffled by Unexplained Force Acting on Space Probes. Essentially, engineers at NASA have noticed slightly unexplained forces on nearly every single spacecraft we’ve sent into the deepest portions of our solar system. Initially, the errors recorded on the Pioneer 10 and 11 were chalked up to errant leaks.
A decade ago, after rigorous analyses, anomalies were seen with the identical Pioneer 10 and 11 spacecraft as they hurtled out of the solar system. Both seemed to experience a tiny but unexplained constant acceleration toward the sun.A host of explanations have been bandied about for the Pioneer anomaly. At times these are rooted in conventional science — perhaps leaks from the spacecraft have affected their trajectories. At times these are rooted in more speculative physics — maybe the law of gravity itself needs to be modified.
There’s some really good ideas floated around in the post. It would seem that there’s some sort of force acting on these vehicles that NASA engineers haven’t and can’t seem to account for in their standard orbital models.
Posted by Clint Ecker 