View Full Version : The Earth and Moon Formed Later Than Previously Thought

2010-Jun-08, 08:50 PM
The Earth and Moon were created as the result of a giant collision between two planets the size of Mars and Venus. Until now it was thought to have happened when the solar system was 30 million years old or approx. 4,537 million years ago. But new research shows that the Earth and Moon must [...]

More... (http://www.universetoday.com/2010/06/08/the-earth-and-moon-formed-later-than-previously-thought/)

2010-Jun-09, 03:49 PM
If the hafnium was produced in one or more of the supernovae that made inputs into the protostellar cloud from which the material comprising the Earth/moon system was produced, how does one compute when the hafnium clock was started? It doesn't seem unlikely that 40 million years wouuld have elapsed before gravity asembled the protostellar cloud.