“The idea that an object weighing thousands of pounds can punch its way into space after spinning in circles on Earth’s surface can be hard to fathom. It might even sound crazy, and the company has a lot to prove to shake its critics. So far it has managed to spin an 11-pound dummy payload at more than 4,000 miles per hour and send it crashing into a steel wall. Between those tests and the edge of space, however, are roughly a hundred miles and a whole lot of air resistance. Never mind the engineering work needed to build a centrifuge 100 yards wide, with an arm strong enough to support a roughly SUV-sized rocket.” Wired: Inside SpinLaunch, the Space Industry’s Best Kept Secret. The company is building a massive centrifuge to accelerate rockets and send them screaming into space. (I wonder if it could be used for humans…)