http://pleasanton.patch.com/articles/moon-and-earth-may-be-younger-than-originally-thought-2

New research using a technique that measures the isotopes of lead and neodymium in lunar crustal rocks shows that the moon and Earth may be millions of years younger than originally thought.

The common estimate of the moon’s age is as old as 4.5 billion years old (roughly the same age as the solar system) as determined by mineralogy and chemical analysis of moon rocks gathered during the Apollo missions. However, Lawrence Livermore National Laboratory scientist Lars Borg and international collaborators have analyzed three isotopic systems, including the elements lead, samarium and neodymium found in ancient lunar rocks, and determined that the moon could be much younger than originally estimated. In fact, its age may be 4.36 billion years old.