i occasionally have questions like "is there anything actually preventing spaceships from going under water?" the answer is, no. space ships can go underwater, just not very deep. it is not the direction of pressure as much the amount of pressure. or asking about how the shape of a nozzle drastically affects how effective a thruster is in different air pressure. this would be a good reason why mavs can have more than 1 g of thrust in space but are much weaker in atmosphere. to find both amateur and professional rocket scientists you can go here. https://www.twitch.tv/directory/game/Kerbal%20Space%20Program yes, you can find rocket engineers from nasa playing this game.