In 1898, Marie Curie discovered the phenomenon of radioactivity, in which unstable atoms lose energy, or decay, by emitting radiation in the form of particles or electromagnetic waves.By 1904 physicist Ernest Rutherford showed how this decay process could act as a clock for dating old rocks.This week, Cherry Lewis of the University of Bristol presented a talk about the history of dating the Earth as part of the BA Festival of Science in York, England.Before so-called radiometric dating, Earth's age was anybody's guess.If, in the year AD 1600, you had asked an educated European how old the planet Earth was and to recount its history he would have said that it was about 6000 years old and that its ancient history was given by the biblical account in Genesis.If you asked the same question of an educated European in AD 1900 you would have received a quite different answer.(Newton pointed out that it must be older than 50,000 years.) A while later, Jean-Baptiste Fourier refined Buffon's investigation.
The answer, unsurprisingly, is absolutely none at all. Ham showdown simply illustrated why challenging creationism is so frustratingly futile.
The best estimates of the age of the Earth are calculated from the ratios of lead and uranium in meteorites found on Earth.
These estimates are verified by Sir Isaac Newton speculated that because "comets occasionally hit the Sun", perhaps the Earth formed from the scattered debris and as such began in a molten state and has been cooling ever since.
In this period a number of comprehensive cosmogonies were proposed.
These were long on armchair speculation and short on substantive supporting evidence.
Once again, he treated the young Earth as a molten sphere, but also took into account the insulating crust.