Besides landing astronauts on the lunar surface in a few years, NASA is faced with the problem of how to replace the International Space Station once it reaches the end of its operational life around 2030. Toward that end, the space agency has signed funded Space Act Agreements with three companies, Blue Origin, Northrop Grumman and Voyager Space, to start design work on commercial space stations. NASA has made an agreement with a fourth company, Axiom Space, to install commercial modules on the ISS as a precursor to its own orbiting space facility. But now a fifth company, called Vast,...