Overview
- The SLS and Orion stack arrived at Launch Complex 39B on March 20 after a weather-delayed rollout from the Vehicle Assembly Building.
- NASA has two-hour launch windows each day from April 1–6, with the first opening at 6:24 p.m. Eastern on April 1 and a limit of four attempts in that period.
- Engineers traced a February upper-stage helium blockage to a dislodged quick‑disconnect seal and completed repairs before approving the return to the pad.
- Officials say hydrogen leak concerns from early February fueling tests have been addressed, and the next full tanking is intended to be on a launch attempt.
- The roughly 10-day lunar flyby will carry Reid Wiseman, Victor Glover, Christina Koch, and Jeremy Hansen, as broader Artemis plans shift to add a 2027 LEO test and use Centaur upper stages for Artemis 4 and 5.