Reaction Engines, one of the brightest prospects in European space plane technology, has big news Monday morning.
BAE Systems, the globetrotting defence and aeronautics giant, just bought 20% of the firm, and it's making a major investment in Reaction Engines' most promising ideas.
The idea is an unpiloted and reusable hypersonic space plane. It's called Sabre. Here's how Reaction Engines describes it: