Gravity is a very familiar force to us here on Earth. We know how it behaves and how it affects us. But where does it come from? We’ll also talk to a NASA astronaut about what it’s like to experience micro-gravity.

More sport science: bats and black eyes
25:25

Sport science: softballs, baseballs, and curve balls
27:12

Is there such a thing as a blue raspberry? And why are raspberries hairy?
26:32