In another venue where I participate this article published at arXiv, Evidence for Correlations Between Nuclear Decay Rates and Earth-Sun Distance, and previous articles from the same source published in recent months, is undergoing a lively discussion.
In a nutshell, a couple of earth based research programs measuring the half lives of radioisotopes have a significant seasonal variation in the raw data values which correlate with distance from the sun. It was brought to our attention by scientific creationists who are constantly on the lookout for things which might dispute the widely accepted yardsticks used to measure geologic age.
I accepted those yardsticks as much as anyone short of being dogmatic about it. Upon reading this I immediately pointed out that significant variation in measured radioisotope half life correlated with distance from the sun, evidenced by seasonal variation in earth based experimental raw data, could be due to instrumentation error. To be fair though I also did some research on radioisotope thermal power supply performance on deep space probes and found there’s a rather large gap between predicted and actual performance. I also pointed out that the measured discrepancies aren’t large enough to turn a 4 billion year old planet into a 6000 year old planet. Still though, if not instrumentation error it raises a legitimate question of what the heck solar generated field or particle emission explains it and what are the bounds for this field or emission effect in the history of the solar system. The scientific creation crew have been predicting a variable half life for a long time and have been roundly dismissed by the scientific establishment at large. It looks like they might have been correct if not in magnitude then at least in principle. Credit where credit is due is my position regardless of the source of inspiration for the hypothesis.
Update: Added RTG performance data of Voyagers I and II in comment #8.