Last week, I rode a rocket-powered plane into space. We thundered down a runway at the Mojave Air & Space Port, then pointed the nose nearly straight up and hurtled toward the stars. As we climbed, the sky started darkening—and out the window to my right, the horizon flipped 90 degrees to the left.
Up, and up, and up we went, the cockpit’s altimeter whirling in dizzying circles. We passed 50,000 feet, and then 60,000 feet, and then—