As a jet was flying over Arizona on a clear day, the copilot was providing his passengers with a running commentary about landmarks over the PA system.

"Coming up on the right, you can see the Meteor Crater, which is a major tourist attraction in northern Arizona. It was formed when a lump of nickel and iron, roughly 150 feet in diameter and weighing 300,000 tons, struck the earth 50,000 years ago at about 40,000 miles an hour, scattering white-hot debris for miles in every direction. The hole measures nearly a mile across and is 570 feet deep."

The lady sitting next to me exclaimed: "Wow, look! It just missed the highway!"