چرا ناسا برای فرستادن فضانوردان از ایالات متحده به فضا به SpaceX نیاز داشت؟

On May 30, 2020, NASA and SpaceX launched astronauts into space from American soil for the first time in almost 10 years. Since the end of the space shuttle program in 2011, NASA has relied on the Russian space program's shuttles to get American astronauts up to the International Space Station — a necessity for furthering research and development when it comes to long-term space travel. But, thanks to the commercial crew program, that's about to change. Here's why it took so long to send a crewed rocket back to space from the US, and why it’s happening on a SpaceX Crew Dragon spacecraft.