NASA has delayed the debut launch of its powerful Space Launch System (SLS) rocket for the Artemis 1 mission to the Moon due to a testing anomaly. What's the updated timeline for this critical flight?
The SLS is undergoing final integrated testing in the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. These checks come before the wet dress rehearsal—still unscheduled—when propellant will be loaded into the rocket's tanks. A successful rehearsal will clear the path for the Artemis 1 launch, sending an uncrewed Orion capsule on a lunar orbit and safe return to Earth.
The mission was originally slated for November 2021. Delays pushed it to mid-February 2022 last October. Now, NASA anticipates a slightly later liftoff from Florida's skies.
During core stage power testing, engineers verified communications between the Orion spacecraft, core stage, boosters, and ground systems. They uncovered an issue with the flight controller on one of the RS-25 engines.
NASA explains: "The flight controller acts as the 'brain' of each RS-25 engine, communicating with the SLS to deliver precise control and internal health diagnostics." "Each has two channels for redundancy. In testing, channel B on engine controller four failed to activate reliably."
Teams conducted further checks and opted to replace the faulty controller. This setback shifts the launch to lunar alignment windows in March and April. The wet dress rehearsal will follow, enabling NASA to announce a firm date—weather permitting.
Artemis 1 will validate Orion's safety systems. Artemis 2 will send four astronauts on a crewed lunar flyby, while Artemis 3 aims to land humans on the Moon after 2025—the first since Apollo 17 in 1972. The SLS is set for at least a decade of lunar missions, each costing around two billion dollars.
