Is radiometric age dating accurate
Kelvin stuck by his estimate of 100 million years, and later reduced it to about 20 million years.
The process of solar nuclear fusion was not yet known to science.
giving a lower limit for the age of the solar system.
It is hypothesised that the accretion of Earth began soon after the formation of the calcium-aluminium-rich inclusions and the meteorites.
After Henri Becquerel's initial discovery in 1896, Marie and Pierre Curie discovered the radioactive elements polonium and radium in 1898; and in 1903, Pierre Curie and Albert Laborde announced that radium produces enough heat to melt its own weight in ice in less than an hour.
Geologists quickly realized that this upset the assumptions underlying most calculations of the age of Earth.
These had assumed that the original heat of the Earth and Sun had dissipated steadily into space, but radioactive decay meant that this heat had been continually replenished.