Can carbon dating go
In principle, any material of plant or animal origin, including textiles, wood, bones and leather, can be dated by its content of carbon 14, a radioactive form of carbon in the environment that is incorporated by all living things.Because it is radioactive, carbon 14 steadily decays into other substances.Scientists at the Lamont-Doherty Geological Laboratory of Columbia University at Palisades, N.
At first, scientists could only date materials to about 5,600 years ago, the half-life of carbon-14.In a similar strategy, scientists examine "cores" of ancient ice removed from the ground in places like Greenland. Ancient bits of coral, analyzed with a technique known as uranium-thorium dating, also help fine-tune carbon dating, Reimer said.But finding and analyzing old materials isn't easy."It would help show whether or not modern man was around at the same time as the last of the Neanderthals," he said."That's a huge question."There's another big question in Guilderson's field: what about dating things to 55,000 years ago – 10 half-lives of carbon-14 – or even further back?
The new dating calibrations will help scientists better analyze ancient climate by looking at prehistoric sediment, said study co-author Tom Guilderson, senior research scientist at Lawrence Livermore National Laboratory.