Just returned from yet another pilgrimage to the Air and Space Museum. For me, the moon rock is always the highlight of the visit. Most of the lunar samples we have today were collected during the six Apollo missions between 1969 through 1972. When I think of the billions of dollars and thousands of human hours spent on the lunar missions, I feel truly privileged that just by taking a short bus ride, I can touch a piece of the same moon. Since the moon has very little geological activity, most of these rocks are as old as the Earth itself (i.e. over 4 billion years old)!