NASA has begun a critical two-day practice countdown for its first crewed mission to the Moon in more than 50 years, marking a major milestone in the United States’ return to deep space exploration. The exercise, known as a “wet dress rehearsal”, is designed to simulate every stage of launch preparations, including loading super-cold propellants into the agency’s powerful new Space Launch System (SLS) rocket, ahead of the long-awaited Artemis II mission .
The rehearsal is being carried out at Kennedy Space Center in Florida, where the 322-foot-tall rocket was rolled out to the launch pad earlier this month. Engineers and launch teams are using the test to closely monitor systems performance, identify any technical issues and fine-tune procedures before committing to an actual liftoff date. The outcome of this countdown practice will play a decisive role in determining when the mission can finally take off.
Artemis II will carry four astronauts — three from NASA and one from the Canadian Space Agency — on a nearly 10-day journey that will send them around the Moon and back to Earth. While the mission will not attempt a lunar landing, it is intended to thoroughly test the spacecraft and life-support systems in deep space, laying the groundwork for future missions that aim to put humans on the Moon’s surface again.
The crew, led by commander Reid Wiseman, has already entered quarantine to reduce the risk of illness ahead of launch. From their base in Houston, the astronauts are closely following the rehearsal as engineers work through a timeline that mirrors launch day as closely as possible. Once the rocket is cleared for flight, the crew will travel to Florida for final preparations.
NASA officials have stressed that such rehearsals are deliberately demanding and often expose problems that must be resolved before flight. In previous tests of the SLS rocket, engineers encountered hydrogen fuel leaks and other technical challenges, prompting delays and additional inspections. The current rehearsal is expected to provide vital data on whether those issues have been fully addressed or if further work is needed.
If the fueling test and countdown simulation are completed successfully, NASA could be in a position to attempt a launch within a narrow window in early February. However, officials have cautioned that any significant technical glitch or unfavourable weather could push the mission back by weeks, underlining the complexity of sending humans beyond low Earth orbit for the first time since 1972.
The Artemis programme represents NASA’s most ambitious human spaceflight effort since the Apollo era. Artemis I, an uncrewed test flight completed in 2022, successfully sent the Orion spacecraft around the Moon, paving the way for the current crewed mission. Artemis II is now seen as the crucial next step before Artemis III, which is planned to land astronauts near the Moon’s south pole later this decade.
Beyond its technical objectives, the mission also carries symbolic weight. It will mark humanity’s return to lunar space after more than half a century and includes historic firsts, with the crew set to include the first woman and the first person of colour to travel beyond Earth orbit.
As NASA presses ahead with the countdown rehearsal, space agencies and governments around the world are watching closely. A successful Artemis II mission would not only restore crewed lunar flight capabilities for the United States but also signal a new era of sustained human presence in deep space, with the Moon serving as a stepping stone for future missions to Mars and beyond.
