/sci/ - Science & Math

Stupid question, but I have a few space problems.
• What exactly... is... that thing they call “The Bends”. How does decompression sickness work in the ocean, and is it the same as an astronaut in space leaving or entering the ISS too quickly? I assume it has to do w/ fluids in general?
• [Follow up question] What would happen to an astronaut who leaves or enters the ISS without prebreathing oxygen/preparing and stuff. Let’s say an astronaut enters the airlock and immediately pressurizes it to equalizes with the station in an instant, would he die?
• Can “air pressure” be used to simulate “gravity”? On titan the gravity is much lower, the air pressure however is much more significant than Earth’s. I’ve heard they balance out and it feels very similar to Earth. With this line of thinking, what would happen if something like the ISS or a bigalow inflate-a-ring were to be pressurized up to 50atm - surely the astronauts wouldn’t feel any gravitational effects of any sort- yet they would feel... tighter? Heavier? What exactly would they feel?

Do (or can) other planets (such as Mars) have crust as heavily differentiated as on Earth, or do you need a mechanism like plate tectonics to create huge differences? I’m thinking specifically of things like basins and plateaus and uplifts/highlands