Two guests: 1) Dr. Douglas Erwin speaks of a huge extinction that almost wiped out life on earth 250 million years ago. 2) Astronaut Tom Jones speaks of the future of the space program.
Two guests: 1) Dr. Douglas Erwin speaks of a huge extinction that almost wiped out life on earth 250 million years ago. 2) Astronaut Tom Jones speaks of the future of the space program.