How is radioactive dating carried out on meteorites and rocks
Ernest Rutherford (of the gold foil experiment) first suggested the ratios of uranium and lead could be used to date rocks in 1905. Aston discovered 212 of the 287 naturally occurring isotopes, including lead.Geologists began using this idea to try and measure the ages of old rocks, but at the time, didn’t know that there were different isotopes of each element, each with different decay rates. Thompson(you might know him for discovering the electron and for his plum pudding model) discovered isotopes of neon using a primitive precursor to a mass spectrometer. Geologists like Alfred Nier began measuring the isotopic ratios of old rocks, providing the basis for Patterson’s discoveries. World War II is a fabulous time period to study the relationship between history and science: scientific discoveries like atomic fission affected the course of history, while big projects like the Manhattan Project would change the very way science is done.* Patterson himself was drafted to work on the Manhattan Project; there, he helped develop the high precision mass spectrometers needed to measure abundances of tiny quantities of isotopes to very high precision.In many cases it is quite difficult to prove whether one method is superior to another: and in this regard, the only way of doing so is to closely examine how each method works and try to find fault with it.In regard to the radiometric dating of rocks, it is known that various different radiometric methods often yield quite discordant dates for the same rock, thus proving that they cannot all be correct.
Comparing these rocks with the products of present erosion, sedimentation, and earth movements, these earliest geologists soon concluded that the time required to form and sculpt the present Earth was immeasurably longer than had previously been thought.
There are at least 67 different uniformitarian (the present is the key to the past) methods of dating the earth other than long-age radiometric dating: each of which yield ages of less than 500 million years.
Yet all these other science-based methods that point to a much younger age than 4.5 billion years for earth's age are ignored or rejected by evolution-believing people with degrees from college who apparently think that nobody (of importance) made them. Yet when asked why they reject all but the oldest science-based dating methods, the answer often given is that (they think) long-age radiometric dating is more reliable and that science settled the matter of the earth's age many years ago.
James Hutton, a physician-farmer and one of the founders of the science of geology, wrote in 1788, “The result, therefore, of our present inquiry is, that we find no vestige of a beginning, — no prospect of an end.” Although this may now sound like an overstatement, it nicely expresses the tremendous intellectual leap required when geologic time was finally and forever severed from the artificial limits imposed by the length of the human lifetime.
By the mid- to late 1800s, geologists, physicists, and chemists were searching for ways to quantify the age of the Earth.