Things That Make Me Go Hmm….
Why do we close our eyes when we sleep? I assume that part of it has to do with keeping stuff out of them when our brain is turned off and we can’t react to keep things (dust, cats) from falling into them. Can you actually sleep with your eyes open? It’s just as dark when the lights are out as it is with your eyes closed, and if it’s more tiring to keep them open what about astronauts sleeping without gravity?