Love Me Like A Rock

Everybody gets excited about whatever's new, but what about what's really, really old?  In this hour of To the Best of Our Knowledge we commemorate geologic time.  We'll meet the scientists who found the oldest object on Earth - a three point four billion year old zircon!  And the Jazz Passengers, who helped them tell their story.  Also, a trip far underground with a geologist who’ll teach us how to read the rocks.