the age of the earth

[BrianSoddingBoru4]

But where did they come up with the range of 4.5 bill years but could be off by 50 million, how did they come to that conclusion?

*sigh* Since you clearly can’t be bothered to read the links provided, I’ll spoon feed you just this once.

You take a rock and figure out which elements are in it. Since all elements decay over time, you can determine the age of the rock by the percentage of daughter isotopes compared to parent isotopes. Doing this thousands and thousands of times gives you better and better information about older and older rocks. When you stop finding older rocks, you have a pretty good idea of the age of the materials that make up the Earth.

The 50MY error factor is partly a matter of the accuracy of measurements, but mostly due to definitions. Geologists have a certain disagreement as to whether ‘age of the Earth’ refers to the accretion, the formation of the core, or the age of the constituent materials.

Boru
____

Yeah, what GS said. Sheesh.