On Thursday, a Silicon Valley startup called SpinLaunch Inc. will reveal the first details of its plans to build a machine meant to hurl rockets into space. To achieve that goal, SpinLaunch has secured $40 million from some top technology investors, said Jonathan Yaney, the founder. The company remains tight-lipped about exactly how this contraption will work, although its name gives away the basic idea. 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.