English: The massive core stage for NASA’s Space Launch System (SLS) rocket is in the B-2 Test Stand at NASA’s Stennis Space Center near Bay St. Louis, Mississippi, for the core stage Green Run test series. NASA and Boeing, the core stage lead contractor, installed the stage into the test stand in January 2020. The core stage Green Run test series is an important step toward safely launching SLS and NASA's Orion spacecraft beyond Earth's orbit forward to the Moon for the agency’s Artemis program. The 212-foot-tall rocket stage -- the largest stage the agency has ever produced -- contains the cryogenic liquid hydrogen and liquid oxygen tanks that will feed four RS-25 rocket engines, along with the vehicle's avionics and flight computers. The comprehensive test campaign will validate the core stage design and ensure it’s ready for the first and future Artemis missions to the Moon.