SpinLaunch, a startup building space catapults, just raised $35 million in funding from investors, including GV, Airbus, and Kleiner Perkins. It previously raised $5 million in seed funding.

So, what exactly are space catapults? In basic terms, they are machines meant to fling objects — such as satellites — into space. SpinLaunch’s objective is to create a cheaper and more sustainable way to launch rockets.

As it stands today, it takes an inordinate amount of energy and capital to lift a rocket from its launchpad. Space exploration companies currently rely on fossil fuels, which can cost hundreds of thousands of dollars for a single launch.

Bloomberg reports, “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.”

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SpinLaunch would use electricity to accelerate a projectile to pierce through gravity and the atmosphere. The company also plans to shorten the amount of time it takes to launch a rocket. CEO Jonathan Yaney said he expects the mechanism to allow for multiple launches a day, compared to the traditional space company lag of several days or weeks in between launches.

SpinLaunch is planning to make its first launch in 2022.