Project Hail Mary

by Andy Weir

Cool thing about pendulums: The time it takes for one to swing forward and backward—the period—won’t change, no matter how wide it swings. If it’s got a lot of energy, it’ll swing farther and faster, but the period will still be the same. This is what mechanical clocks take advantage of to keep time. That period ends up being driven by two things, and two things only: the length of the pendulum and gravity.

“Believe it or not, light has momentum,” I said. “It exerts a force. If you were out in space and you turned on a flashlight, you’d get a teeny, tiny amount of thrust from it.”

Everything emits light. The temperature of the object defines the wavelength of light emitted.

Human beings have a remarkable ability to accept the abnormal and make it normal.

There’s nothing special about the number 10. We have ten unique digits because we have ten fingers.

Sometimes, the stuff we all hate ends up being the only way to do things.

Do you believe in God? I know it’s a personal question. I do. And I think He was pretty awesome to make relativity a thing, don’t you? The faster you go, the less time you experience. It’s like He’s inviting us to explore the universe, you know?”

“You face is leaking.” I wipe my eyes. “Human thing. Don’t worry about it.”