That’s one of the things that make them so fascinating to most people.To be holding or looking at something that lived millions of years ago… However, have you ever asked yourself or anyone else, “What is it about a dinosaur bone that makes it so old?” In other words, what about the bone itself makes it old?I’ve asked many people that question and the response is usually a short period of silence followed by the shrugging of the shoulders.Radioactive decay allows geologists and physicists to measure the age of ancient fossils, rocks and even the Earth.
All radioactive atoms decay to become a more stable kind of atom.
The original radioactive atom is known as a parent isotope, while the atom produced by the decay process is known as a daughter isotope. For example Uranium-235 and Uranium-238 are both Uranium atoms with the same number of protons, but they have a different number of neutrons.
The number used to identify the isotope refers to the total number of particles in the nucleus of each atom.
Radiometric dating is possible because the radioactive decay of large numbers of radioactive atoms follows a predictable pattern.
This predictability allows scientists to measure the age of an object if they can work out how many radioactive atoms were originally present.