# Radiocarbon dating is accurate to about how many years ago

### Radiocarbon dating is accurate to about how many years ago

Question: "Is carbon dating a reliable method for determining the age of things?" Answer: Carbon dating, or radiocarbon dating, like any other laboratory testing technique, can be extremely reliable, so long as all of the variables involved are controlled and understood.

For this reason, it’s preferable to date objects using multiple methods, rather than relying on one single test.For an example, when they tried to get the carbon dating for presence of Aboriginal people in Australia they get to the number 40,000. Why is that 40,000 years limit for carbon dating methods?Carbon-14 makes up about 1 part per trillion of the carbon atoms around us, and this proportion remains roughly constant due to continual production of carbon-14 from cosmic rays.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.So by measuring the C-14 level we work out how many half lives old the sample is and therefore how old it is.

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.

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.

Carbon dating is reliable within certain parameters but certainly not infallible.

When testing an object using radiocarbon dating, several factors have to be considered: First, carbon dating only works on matter that was once alive, and it only determines the approximate date of death for that sample.

For example, a steel spearhead cannot be carbon dated, so archaeologists might perform testing on the wooden shaft it was attached to.