The Ice Age in the Far North

If you play around with the amount of sunlight and heat hitting the earth, you can either grow a glacier or make one go away. And this was figured out actually by a guy sitting in a prisoner of war camp in world war one. We like to sort of think of our earth as is orbiting in a particular way, and it's always been that way and it's never going to change. That's just not right, right? Because we've got all these other planets out there. So we've got the gravitational effects of the sun, but then there's jupiter parked a few orbits out there, and it also affecting us.