 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. And so this is a problem that needs to be solved. Notice, I didn't say it makes it impossible to go to other planets. I said it's a problem that needs to be solved. And humans are adaptive and tool makers. We can solve it. We just have to think about it and work it out and do it.