How many years can carbon dating go back

15 Oct

The half life of carbon-14 is about 5,700 years, so if we measure the proportion of C-14 in a sample and discover it's half a part per trillion, i.e.

half the original level, we know the sample is around one half life or 5,700 years old.

The method was developed by Willard Libby in the late 1940s and soon became a standard tool for archaeologists.

Libby received the Nobel Prize in Chemistry for his work in 1960.

This isn't a fundamental limit as more accurate measurements could go further back, but at some point you'd simply run out of C-14 atoms.

With our current kit 40-50K years is about the limit.

Note that, contrary to a popular misconception, carbon dating is not used to date rocks at millions of years old.

The trouble is that after 40,000 years there is under 1% of the original C-14 left, and it becomes too hard to measure it accurately.So, we have a “clock” which starts ticking the moment something dies.Obviously, this works only for things which were once living.We will deal with carbon dating first and then with the other dating methods.Carbon has unique properties that are essential for life on Earth.