Start How old is earth based on radiometric dating

How old is earth based on radiometric dating

At some point in the early history of Earth, a planetoid the size of Mars crashed into our planet.

Since they decay in a very known rate, these isotopes can be measured to determine how long the elements have existed.

And by studying different meteorites from different locations in the Solar System, scientists know that the different planets all formed at the same time.

Small particles of dust collected together into larger and larger objects – pebbles, rocks, boulders, etc – until there were many planetoids in the Solar System.