Radiocarbon watch: Cornell have redated a Hellenistic-era shipwreck. That much interests me little, as compared - say - to the Late-Bronze Canaanites/Ugaritics. More interesting is how the redate has forced Cornell to confront the radiocarbon curves of the era.
First up is that the wood had been treated by polyethylene glycol which is, of course, a hydrocarbon... made in our twentieth-century. Which carbon is the carbon of the time? Apparently glycol contamination is a problem with older museum-preserved woods. So, this team was able to remove that. (The press-release implies we shun hydrocarbons as preservatives anymore but hey, now we might be able to use glycol once again...)
It seems our Sun was weak before the wreck, when the trees felled to build the ship were still alive. At ~360 BC, our nitrogen took in more neutrons than it normally would, which decayed into carbon-14. Thus, it blew the carbon-curve. I don't think the spike was quite dramatic enough, or the planks wide enough, to leave a ring-by-ring record and anyway the ship could have been afloat for some years, hence why the date of the wreck itself remains a mere estimate (as I noted I don't really care).
I care more about 360 BC. Aurora?
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