Hello! I'm not entirely sure this is very "scientific", but I have an idea that I would like some feedback on. I remember reading an article related to radioactive decay varying with the rotation and distance from the sun on Phys.org a few years back (http://phys.org/news202456660.html) and was pretty intrigued by the idea. They state the fluctuation is roughly a "tenth of a percent", which is pretty uneventful in the large scale of daily life. In a seemingly unrelated story about the Pioneer Anomaly (http://phys.org/news/2012-07-source-anomaly.html) I had a theory that could possibly be tested. Perhaps radioactivity is more variable than we understand since we have a pretty steady distance from the sun, and also are under the influence of the heliosphere at all times. My question or idea or hypothesis is: could we use the data from either the temperature, power output, or maybe the deceleration effect of the radioactive thermoelectric generators on board the viking spacecraft(s) to calculate any statistically significant fluctuations in the decay rates near the edge of the solar system? And would it be useful? Just a thought I've had for a while; I thought maybe someone had some input or solid reasoning that will get this out of my 'hypothesis box'.