Now, you might think NASA would ask industry for solutions to this problem. After all, United Launch Alliance was developing a more powerful upper stage for its Vulcan rocket, the Centaur V, that used the same propellant as the core stage of the SLS rocket. And Blue Origin was also developing a powerful upper stage engine, the BE-3U, powered by hydrogen. These options were cheaper, available, and … summarily ignored.
10 years, billions of dollars, and not much to show for it
Congress, smelling jobs, wanted NASA to develop a brand new upper stage. So in 2016, lawmakers allocated $85 million for preliminary work on the upper stage, and
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