No, I don't regularly read slashdot and no one asked the question here yet so...
I don't find it surprising though that that is the first question that would pop into most peoples heads as dating is the most popularly know use of decay measurements.
Unlikely. The distance between the Earth and the Sun varies throughout the year, but it all evens out. When you are trying to figure out the age of a sample that may be thousands of years old, these variations are just noise and nothing significant.
What would be interesting is how the decay rate on the nuclear generators aboard Pioneers 10 & 11 and Voyagers 1 & 2 have varied as they traveled away from the Sun over the past 30-40 years. See:
You are to be commended to think like that. But past evidence suggests we'd more likely use the knowledge to increase nuclear decay and make improved weapons.
Given that the nuclear batteries for various outer-system probes still work properly, I think it's far less likely that an increase is possible. Standard decay rates seem likely to be close to the maximum possible, since only slowing was reported. I'm not sure if anyone's used nuclear-powered spacecraft closer to the sun; it doesn't seem likely, since solar power is plentiful there.
Ulysses was in the news in 1996-1997 because NASA's Cassini-RTG decision was being criticized. The argument was that NASA's can't-use-solar-at-the-distance-of-Saturn argument didn't hold water in light of the fact that NASA even chose to put an RTG on a Sun explorer.
it doesn't seem likely, since solar power is plentiful there.
That was the crux of the NASA-can't-be-trusted argument.
Still, the idea that low energy EM can affect nuclear decay even that strongly suggests new physics that might lead to more EM-nuclear coupled devices. I'm sure it's far too early for reasonable speculation, but I'm excited. :)
Unexplained periodic fluctuations in the decay rates of Si-32 and Ra-226 have been reported by groups at Brookhaven National Laboratory (Si-32), and at the Physikalisch-Technische-Bundesandstalt in Germany (Ra-226). We show from an analysis of the raw data in these experiments that the observed fluctuations are strongly correlated in time, not only with each other, but also with the distance between the Earth and the Sun. Some implications of these results are also discussed, including the suggestion that discrepancies in published half-life determinations for these and other nuclides may be attributable in part to differences in solar activity during the course of the various experiments, or to seasonal variations in fundamental constants.
