Unique view of NASA Artemis II moon rocket rollback with US Flag and Countdown Clock in view. NASA’s crawler-transporter 2, carrying NASA’s Artemis II SLS (Space Launch System) rocket with the Orion spacecraft secured to mobile launcher 1, rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to troubleshoot the flow of helium to the rocket’s upper stage, the interim cryogenic propulsion stage. Once complete, the SLS rocket will roll back to Launch Complex 39B to prepare to launch four astronauts around the Moon and back for the Artemis II test flight. Credit: Ken Kremer / Space UpClose
KENNEDY SPACE CENTER, FL – NASA’s SLS (Space Launch System) and Orion spacecraft mega moon rocket for the Artemis II crewed moonshot mission has begun its rollback from launch pad 39B to the VAB at 9:38 a.m. EST, Feb. 25, at NASA’s Kennedy Space Center in Florida – to fix the helium flow interruption issue detected in the ICPS upper stage during testing overnight Feb. 21 at Launch Complex 39B.
Rolling back from Launch Pad 39B to the Vehicle Assembly Building at NASA Kennedy was delayed a few days by poor weather
NASA’s Artemis II SLS (Space Launch System) rocket with the Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to troubleshoot flow of helium to rocket’s interim cryogenic propulsion stage (ICPS) upper stage. Once complete SLS rocket will roll back to Launch Complex 39B to launch four astronauts around the Moon and back for Artemis II test flight. Credit: Ken Kremer / Space UpClose
The approximately 4-mile trek is expected to take up to 12 hours – similar to rollout on Jan. 17.
NASA’s Artemis II SLS rocket and Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to fix flow of helium to rocket’s upper stage. Credit: Ken Kremer / Space UpClose
Once back in the VAB, teams will immediately begin work to install platforms to access the area of the helium flow issue in the rockets ICPS upper stage to diagnose and fix it
NASA Artemis II will launch four astronauts around the Moon and back on a 10 days test flight – on the first mission to send humans to the Moon in over 50 years since Apollo 17 in Dec. 1972.
NASA’s Artemis II SLS rocket and Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to fix flow of helium to rocket’s upper stage. Credit: Ken Kremer / Space UpClose
Enjoy our Gallery of Rollback photos for Space UpClose from the team of Ken Kremer and Jean Wright – which will be posted in several galleries.
The Helium forced the rollback which also forced an Artemis II launch delay from early March to the NET early April window – TBD.
A livestream of the rollback will be streamed on the agency’s YouTube channel.
NASA’s Artemis II SLS rocket and Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to fix flow of helium to rocket’s upper stage. Credit: Ken Kremer / Space UpClose
While in the assembly building, technicians will not just troubleshoot and fix the helium flow issue to the rocket’s upper stage, but also used the time to simultaneously replace batteries on the rocket’s upper stage, core stage, and solid rocket boosters as well as service its flight termination system.
The quick timing of the rollback also preserves NASA the option of preserving the best possibility to launch Artemis II in the April launch window – which extends from April 1 to April 6
NASA’s Artemis II SLS rocket and Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to fix flow of helium to rocket’s upper stage. Credit: Ken Kremer / Space UpClose
This unfortunate problem comes right after NASA completed a fully successful cryogenic fueling test and simulated launch countdown test of its SLS (Space Launch System) mega moon rocket during the 2nd attempt at a wet dress rehearsal (WDR) on Thursday, Feb. 19 at the agency’s Kennedy Space Center in Florida.
Details about the Helium clog here from NASA Administrator Jared Isaacman
– The ICPS helium bottles are used to purge the engines, as well as for LH2 and LOX tank pressurization. The systems did work correctly during WDR1 and WDR2.
– Last evening, the team was unable to get helium flow through the vehicle. This occurred during a routine operation to repressurize the system.
– We observed a similar failure signature on Artemis I.
– The Artemis II vehicle is in a safe configuration, using ground ECS purge for the engines versus the onboard helium supply.
– Potential faults could include the final filter between the ground and flight vehicle, located on the umbilical, though this seems least likely based on the failure signature. It could also be a failed QD umbilical interface, where similar issues have been observed. It could also be a failed check valve onboard the vehicle, which would be consistent with Artemis I, though corrective actions were taken to minimize reoccurrence on Artemis II.
Regardless of the potential fault, accessing and remediating any of these issues can only be performed in the VAB.
Artemis II Mission Availability
…………….
NASA’s Artemis II SLS rocket and Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to fix flow of helium to rocket’s upper stage. Credit: Ken Kremer / Space UpCloseNASA’s Artemis II SLS rocket and Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to fix flow of helium to rocket’s upper stage. Credit: Ken Kremer / Space UpClose
NASA’s Artemis II SLS rocket and Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to fix flow of helium to rocket’s upper stage. Credit: Ken Kremer / Space UpCloseNASA’s Artemis II SLS rocket and Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to fix flow of helium to rocket’s upper stage. Credit: Ken Kremer / Space UpClose
NASA’s Artemis II SLS rocket and Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to fix flow of helium to rocket’s upper stage. Credit: Ken Kremer / Space UpCloseNASA’s Artemis II SLS rocket and Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to fix flow of helium to rocket’s upper stage. Credit: Ken Kremer / Space UpCloseNASA’s Artemis II SLS (Space Launch System) rocket with the Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to troubleshoot flow of helium to rocket’s interim cryogenic propulsion stage (ICPS) upper stage. Once complete SLS rocket will roll back to Launch Complex 39B to launch four astronauts around the Moon and back for Artemis II test flight. Credit: Ken Kremer / Space UpCloseNASA’s Artemis II SLS (Space Launch System) rocket with the Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to troubleshoot flow of helium to rocket’s interim cryogenic propulsion stage (ICPS) upper stage. Once complete SLS rocket will roll back to Launch Complex 39B to launch four astronauts around the Moon and back for Artemis II test flight. Credit: Ken Kremer / Space UpCloseUnique view of NASA Artemis II moon rocket rollback with US Flag and Countdown Clock in view. NASA’s crawler-transporter 2, carrying NASA’s Artemis II SLS (Space Launch System) rocket with the Orion spacecraft secured to mobile launcher 1, rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to troubleshoot the flow of helium to the rocket’s upper stage, the interim cryogenic propulsion stage. Once complete, the SLS rocket will roll back to Launch Complex 39B to prepare to launch four astronauts around the Moon and back for the Artemis II test flight. Credit: Ken Kremer / Space UpCloseNASA’s Artemis II SLS (Space Launch System) rocket with the Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to troubleshoot flow of helium to rocket’s interim cryogenic propulsion stage (ICPS) upper stage. Once complete SLS rocket will roll back to Launch Complex 39B to launch four astronauts around the Moon and back for Artemis II test flight. Credit: Ken Kremer / Space UpCloseNASA’s Artemis II SLS rocket and Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to fix flow of helium to rocket’s upper stage. Credit: Ken Kremer / Space UpCloseKen Kremer of Space UpClose with Moon above attend rollback of NASA Artemis II on Feb. 25, 2026, to the VAB at NASA’s Kennedy Space Center in Florida. Credit: Ken Kremer / Space UpClose
Jean Wright of Space UpClose attend rollback of NASA Artemis II on Feb. 25, 2026, to the VAB at NASA’s Kennedy Space Center in Florida. Credit: Ken Kremer / Space UpClose
Ken Kremer and Jean Wright of Space UpClose attend rollback of NASA Artemis II on Feb. 25, 2026, to the VAB at NASA’s Kennedy Space Center in Florida. Credit: Ken Kremer / Space UpCloseKen Kremer and Jean Wright of Space UpClose attend rollback of NASA Artemis II on Feb. 25, 2026, to the VAB at NASA’s Kennedy Space Center in Florida. Credit: Ken Kremer / Space UpClose
Ken Kremer and Jean Wright of Space UpClose reporting on the Artemis II launch campaign activities from NASA Kennedy Space Center Press Site at the Countdown Clock. Credit: Ken Kremer / Space UpCloseNASA’s Artemis II SLS rocket and Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to fix flow of helium to rocket’s upper stage. Credit: Ken Kremer / Space UpClose
NASA’s Artemis II SLS rocket and Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to fix flow of helium to rocket’s upper stage. Credit: Ken Kremer / Space UpClose
NASA’s Artemis II SLS rocket and Orion spacecraft rolls back Wednesday, Feb. 25, 2026, to the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida to fix flow of helium to rocket’s upper stage. Credit: Ken Kremer / Space UpClose
Watch for Ken’s continuing onsite coverage of NASA, SpaceX, ULA, Boeing, Lockheed Martin, Northrop Grumman and more space and mission reports direct from Kennedy Space Center and Cape Canaveral Air Force Station in Florida and Wallops Flight Facility in Virginia. Stay tuned here for Ken's continuing Earth and Planetary science and human spaceflight news. Dr. Kremer is a research scientist and journalist based in the KSC area, active in outreach and interviewed regularly on TV and radio about space topics. Ken’s photos are for sale and he is available for lectures and outreach events.
CAPE CANAVERAL/KENNEDY SPACE CENTER, FL – On March 25, 2026 I was interviewed live by Fox 35 Orlando about “NASA unveils timeline for $20 billion moon base project” and NASAs new plans to establish a moon base with astronauts at the lunar South Pole – that were announced on March 24 by new NASA Administrator Jared Isaacman. Also discussed – How,
KENNEDY SPACE CENTER, FL – After a few weeks of repairs and high winds in the final hours forcing another 4 hours of delays that stretched into Friday, March 20, NASA at last completed the 2nd rollout of the agency’s Artemis II SLS Moon rocket and Orion spacecraft from the Vehicle Assembly Building (VAB) back out to launch pad 39B
