COSMOS khichdi/highlights/revision/cheat sheet.

[TLK]

Re: COSMOS khichdi/highlights/revision/cheat sheet.

@Southie

.A prof hamilton i thi k hired a Grad student Patterson to measure uranium and lead in zirconium. Uranium was trace. Grad student b measured uranium. Repeatable results. Patterson pb was inconsistent. Contamination. Finally measured it in clean room. Then measure lead and uranium content from meteorite. And Calculated earth age go be 4.5 billion yrs old.

Sorry for cutting and pasting off Google, but this explains in a much better and simpler way.

As Patterson explained in an interview in the year that he died, the Canyon Diablo meteorites didn’t contain any uranium, a metal that radioactively decays into lead at well-established rates taking hundreds of millions of years. Other rocks contained both lead and uranium.
So, by reporting the ratio of lead types found in these pristine meteorites and comparing them to lead ratios found in the other rocks on the Earth and other meteorites, Patterson could calculate the age of the solar system, when the Earth formed, to be 4.55 billion years old, give or take 70 million years.