Cold Snap Forces NASA to Push Key Fueling Run, Tightening Artemis II’s February Window

NASA delayed a critical wet dress rehearsal for its crewed Artemis II flight after an unseasonable cold snap in Florida raised unacceptable risk to cryogenic handling. The full fueling and countdown practice was rescheduled for the evening of Feb. 2 and will exercise ground systems and vehicle interfaces while loading roughly 700,000 gallons of liquid oxygen and liquid hydrogen into the SLS core stage and upper elements. Teams will carry the run into the automatic stop point at T‑29 seconds to validate automated cutoff and abort logic and to verify seals, valves and thermal behavior under operational conditions. The SLS and mobile launcher recently completed their transfer to Launch Complex 39B, marking the start of an intensive campaign of integrated checkouts that culminate in this wet dress rehearsal — the primary technical gate before any launch date is locked. Artemis II will carry four crew members on a short lunar sortie designed to validate Orion, life support and deep‑space procedures; the mission profile uses a free‑return geometry and relies on infrastructure such as the Deep Space Network for beyond‑Earth communications. Mission managers stress that the rehearsal’s outcome is pivotal: a clean run preserves a small set of February opportunities (previously flagged dates include Feb. 8, 10 and 11), while anomalies could require additional rehearsals and likely push the flight into March or later. Changes informed by the earlier uncrewed campaign — including revised fueling procedures, updated ground connections and a redesigned valve that had been troublesome — reduce the probability of repeat problems but do not eliminate cryogenics’ sensitivity to temperature and hardware behavior. NASA plans to stream the rehearsal, with formal viewing links issued shortly before operations and commentators guiding audiences through the sequence. The reschedule tightens the calendar between rehearsal completion and possible liftoff, compressing time available for inspections, troubleshooting and any necessary repeat runs. For industrial partners and downstream missions, integrated test results will influence modifications, procurement schedules and the cadence of follow‑on cargo and crew flights; setbacks could ripple into Artemis 3 surface‑return planning. Over the next 48–72 hours, engineers and managers will assess whether the program can sustain a February cadence or must accept a later launch date, prioritizing mission assurance over calendar pressure.