The sun, the planets and asteroids in our solar system were all formed about 4,560 million years ago from a "common ancestor", a Science Week Ireland lecture was told in Dublin last night. Dr Ian Sanders, senior lecturer, Department of Geology, TCD, said the chemical composition of chondritis, which are one type of meteorites, and the sun are identical, so they are believed to have started from a "uniform batch of material".
The lecture discussed the "processes of what happened right at the beginning" of the solar system.
Dr Sanders explained: "The solar system was formed from part of the galaxy which was dusty and gassy." These "dust clouds" become unstable and fold in on themselves into a central lump, which becomes a star.
Around this is a revolving disk of dust, he said, which coagulates to form planets.
He said meteors are the fragments of rock which have broken off when asteroids collide in space. Asteroids themselves form from the dust that accumulates into planets.
Meteors can be dated by measuring the extent of radioactive decay of uranium, one element found in the meteor's make-up.
Meteors formed in these processes "have, fortuitously, remained the same ever since".
He will talk on the same topic, but aimed at a more popular audience, children included, on Saturday at 11 a.m. in TCD's museum building.