It was hard to become an astronaut. Not anywhere near as much physical training as people imagine, but a lot of mental training, a lot of learning. You have to learn everything there is to know about the Space Shuttle and everything you are going to be doing, and everything you need to know if something goes wrong, and then once you have learned it all, you have to practice, practice, practice, practice, practice, practice, practice until everything is second nature, so it's a very, very difficult training, and it takes years.
Sally RideThe pressure suit helps if something goes wrong during launch or re-entry - astronauts have a way to parachute off the shuttle. The suits protect you from loss of pressure in case of emergency.
Sally RideSuppose you came across a woman lying on the street with an elephant sitting on her chest. You notice she is short of breath. Shortness of breath can be a symptom of heart problems. In her case, the much more likely cause is the elephant on her chest. For a long time, society put obstacles in the way of women who wanted to enter the sciences. That is the elephant. Until the playing field has veen leveled and lingering stereotypes are gone, you can't even ask the question.
Sally RideSo most astronauts are astronauts for a couple of years before they are assigned to a flight.
Sally Ride