In fact, this form of dating has been used to date the age of rocks brought back to Earth from the moon.
So, we see there are a number of different methods for dating rocks and other non-living things, but what if our sample is organic in nature?
Radiocarbon dating, also known as carbon-14 dating or simply carbon dating, is a method used to determine the age of organic material by measuring the radioactivity of its carbon content.
By anyone's standards, 50 billion years is a long time.
For example, uranium-lead dating can be used to find the age of a uranium-containing mineral.
It works because we know the fixed radioactive decay rates of uranium-238, which decays to lead-206, and for uranium-235, which decays to lead-207.
Because plants use carbon dioxide for photosynthesis, this isotope ends up inside the plant, and because animals eat plants, they get some as well.
When a plant or an animal dies, it stops taking in carbon-14.