 And they used those as a shelter when there was going to be a solar storm. So the astronauts could go into that module, and the batteries acted as a shield. So they were thinking about the problem. I'm not sure that's going to solve it, you know, because that's only used when you know a solar storm is coming. But cosmic rays are random. And we're learning that they definitely cause vision problems and other problems for the astronauts in space. And so that means you need to protect them all the time.