NASA’s mega moon rocket gets key upgrades for upcoming crewed mission

By Trevor Mogg Published September 18, 2025

NASA is gearing up to send its first astronauts toward the moon in five decades.

The Artemis II mission is currently set for early next year and will use NASA’s next-generation SLS rocket and Orion spacecraft.

Although none of the four crew members will be stepping foot on the lunar surface, they will come as close as 4,000 miles (around 6,440 km) of it before flying around the moon and returning home.

The much-anticipated mission will take about 10 days from launch to splashdown, making it 15 days shorter than the uncrewed Artemis I mission in 2022 that operated as a test run for Artemis II.

NASA has just shared an update on its preparations for Artemis II, focusing on some of the improvements made to the SLS rocket and the Orion since the Artemis I mission.

As with the SLS rocket’s first flight three years ago, the 322-feet-tall (98-meter) still comprises a central core stage, four RS-25 main engines, two five-segment solid rocket boosters, the ICPS (interim cryogenic propulsion stage), a launch vehicle stage adapter to hold the ICPS, and an Orion stage adapter connecting SLS to the Orion spacecraft.

NASA said that as the SLS rocket heads skyward next year, it will jettison the spent boosters four seconds earlier than it did in the Artemis I ascent. Dropping the boosters a little earlier will reduce the weight that the core stage needs to carry after booster separation. The saved weight should allow the rocket to carry more cargo or heavier payloads to space, and the Artemis II flight will allow engineers to compare data to confirm their calculations.

The SLS rocket’s maiden flight in the Artemis I mission experienced unsteady airflow that caused higher-than-expected vibrations near the solid rocket booster attachment points, and so NASA has added a pair of six-foot-long aerodynamic surfaces for a smoother ascent.  

Upgrades to the flight system include optical targets fitted to the ICPS that will function as visual cues for the four Orion astronauts when they come to manually pilot the spacecraft around the rocket’s upper stage, at the same time practicing maneuvers to gather data for docking operations for the future Artemis III mission. During that mission, which is currently set for 2027, the Orion will link up with SpaceX’s Starship spacecraft for a crewed lunar landing — the first since 1972.

The rocket’s navigation system has also been enhanced — alongside improvements to its communications capabilities — by repositioning antennas on the rocket to ensure continuous communication with NASA personnel on Earth.

Notably, the emergency abort system has been refined to add a time delay to the self-destruct sequence. This will give the Orion and its crew more time to move clear of the rocket in the event of an abort, better protecting the astronauts from any destructive actions that occur soon after.

Other improvements include work on the core stage power distribution control unit, which controls power to the rocket’s other electronics and protects it from electrical hazards.

“While we’re proud of our Artemis I performance, which validated our overall design, we’ve looked at how SLS can give our crews a better ride,” said John Honeycutt, NASA’s SLS program manager. 

Honeycutt added that some of the changes have been made in response to specific Artemis II mission requirements, while others are the result of ongoing analysis and testing, as well as insights gained from the Artemis I voyage.

The Artemis II crew includes NASA’s Reid Wiseman, Victor Glover, and Christina Koch, together with Jeremy Hansen of the Canadian Space Agency. The four astronauts have been in training since they were announced as the Artemis II crew in 2023.