3 - Imagineers consulted astronauts when creating Space Mountain.
We know that Disney is known for the level of detail that the imagineers go through in order to conduct research and create perfect experiences for guests with every detail considered. This is one of the reasons why the attractions are so immersive and beloved for years and years. When it came to building and constructing the Space Mountain experience, Gordon Cooper was consulted. He is a real astronaut that has gone out in space, and provided a consultative role to help make the best experience possible. We can see that paid off with how popular the attraction continues to be after all of these years.