NASA's massive Space Launch System (SLS) rocket, poised to propel the Orion spacecraft around the Moon in the Artemis 1 mission, is gearing up for a critical "wet dress rehearsal" at the launch pad in February. A successful test could pave the way for liftoff as early as March.
As the cornerstone of NASA's ambitious Artemis program—aiming to return humans to the lunar surface for the first time since Apollo—Artemis 1 represents a monumental engineering achievement. For months, the SLS, NASA's new super-heavy-lift powerhouse, has endured rigorous testing to validate every component under flight-like stresses.
Most recently, on January 11, engineers at Kennedy Space Center in Florida successfully retracted and extended the access arm to the Orion spacecraft. This crew access arm ensures safe astronaut boarding for future missions and supports technicians during assembly and tests in the Vehicle Assembly Building (VAB).
The SLS core stage, also in the VAB, recently completed key tests: replacing and verifying one of four RS-25 engine controllers, confirming communication between flight computers, engine controllers, and core stage systems, and simulating engine gimballing maneuvers expected in flight.
Next, NASA will conduct a second countdown test to verify SLS and Orion integration and response.
In February, the stacked SLS and Orion will roll out to Launch Pad 39B for the wet dress rehearsal. Engineers will load the core stage engines with supercold liquid hydrogen and liquid oxygen, monitor the fueling process, and then safely drain the propellants—mimicking launch day procedures.
If all benchmarks are met, Artemis 1 could launch in March or April, weather permitting. This uncrewed test flight will validate Orion's safety for deep space. Artemis 2 will follow with a four-person crew orbiting the Moon, while Artemis 3 targets crewed lunar landings after 2025.
