A space catapult is a theoretical alternative to rockets, and apparently Airbus and Google are interested.

Rather than using propellants like kerosene and liquid oxygen to ignite a fire under a rocket, SpinLaunch plans to get a rocket spinning in a circle at up to 5,000 miles per hour and then let it go—more or less throwing the rocket to the edge of space, at which point it can light up and deliver objects like satellites into orbit.