@lydiaconwell you could, but imagine the occasional solar wind whistling across the top like breath over a bottle, or maybe a warp-speed version of having one window of your car rolled down. Maybe they just don't do it because the noise is too annoying. Picard (at the top of his voice): "I SAID MAKE IT SO! WILL SOMEBODY CLOSE THE ROOF!"

@brian_burton That's how Picard lost his hair. He was on the maiden voyage.

@lydiaconwell @brian_burton My dad used to tell kids he lost his hair because he didn't wear a helmet riding his bike. It was effective propaganda.