Engineers have completed filling the core stage liquid hydrogen tank, and have moved into the replenish phase. Core stage liquid oxygen fast fill is still underway. Although the LH2 tank is larger than the LOX tank, LOX is denser than LH2 and takes longer to load.

Teams continue to work toward a two-hour launch window that opens at 1:04 a.m. EST, from Launch Pad 39B at NASA’s Kennedy Space Center in Florida.

Core Stage Liquid Hydrogen in Replenish