Isotope dating meteorites
As a result, the interiors of larger bodies experienced substantial melting, with consequent physical and chemical changes to their constituents.Smaller bodies, on the other hand, generally radiated away this heat quite efficiently, which allowed their interiors to remain relatively cool.First, when the solar system began to form, it was composed of gas and fine-grained dust.
Although it is apparent that millions of years worth of decay—at today’s slow rates—has occurred in isotope decay systems, it is clear that the decay occurred rapidly, during a period of extreme acceleration.
Available evidence indicates that asteroids and comets are leftovers of the intermediate stages of the aggregation mechanism.
They are therefore representative of bodies that formed quite early in the history of the solar system.
Though the measurements of these elements are very precise, the assumptions upon which their usefulness as a clock rests are questionable at best.
In a article on Brennecka’s findings, Gerald Wasserburg, emeritus professor of geology at Caltech, commented, “Everybody was sitting on this two-legged stool claiming it was very stable, but it turns out it’s not.” To be fair, however, it wasn’t “everybody” who claimed this.