Why NASA’s hopes of returning to the moon before China gets there hinge on SpaceX

As SpaceX’s Starship rocket thundered into the South Texas sky this week, a crowd of employees outside mission control began to chant, “U-S-A, U-S-A!” It was the second successful test flight after a string of fiery failures for Starship, bringing Elon Musk’s rocket company a step closer to its goal of carrying NASA astronauts back to the moon. Yet, the hurdles ahead seem as large and daunting as the 400-foot-tall launch system.