“‘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.” “I didn’t know that.” “Now you do. And a teeny-tiny thrust on a teeny-tiny mass can be an effective form of propulsion.’”
—Andy Weir “Project Hail Mary” (2021)














