Tesla's new Roadster hung almost upside down 65 feet off the ground, let go, and caught itself before it landed. The only thing it used to stop the fall was air. Without the thrusters, that's a bad two seconds. From 65 feet, about six stories, a car hits the pavement doing roughly 44 mph. Nobody was inside. Elon said the car drove itself for the demo "to make sure we don't kill anyone." Watch the readout in the bottom left as it drops. It jumps to 3.1 G at 31 feet as the thrusters fire, which is about how hard you get pressed into your seat at the bottom of a big roller coaster drop. While that's happening, attitude thrusters roll the car right side up and thrusters at the corners fire straight down to set it on its wheels. The tanks hold about 250 kg of ordinary air, crammed into two carbon-wrapped pressure vessels totaling 600 liters, the same kind of tank SpaceX flies on its rockets. That works out to air roughly 340 times denser than what you're breathing, stored at several hundred atmospheres. Tesla says it leaves the nozzles faster than the speed of sound and the system puts out more than 80 kN, enough force to hold up over 8,000 kg. The white cloud it lands in comes from the air too. Gas expanding that violently gets cold enough to turn the moisture in the night air into fog on the spot. Nothing on the car is burning. And the tanks refill themselves. Elon says the Roadster can pump them back up on its own, which means the propellant for that six-story catch was the same air you're breathing right now.