Artemis II (April 1–11, 2026) was a crewed flyby of the Moon and first crewed flight of the NASA-led Artemis program. It was the first crewed flight beyond low Earth orbit (LEO) since Apollo 17 in 1972 and the only crewed flight beyond LEO not part of the Apollo program. It was the first crewed flight of the Space Launch System (SLS) and of the Orion spacecraft, named Integrity by the four-person crew.
The mission was a test flight supporting the Artemis IV mission to return humans to the lunar surface. Originally designated Exploration Mission-2 (EM-2) and intended to support the canceled Asteroid Redirect Mission, its objectives were revised after the establishment of the Artemis program in 2017. The mission's primary goal was to validate the Orion spacecraft's systems, crew operations, and mission procedures ahead of sustained lunar exploration in future Artemis missions. Artemis II's mission objectives were similar to those of Apollo 8 in 1968, the first crewed lunar flight of the Apollo program, while its free-return trajectory resembled that flown by Apollo 13 in 1970.
Among the four crew members, Victor Glover became the only person of color, Christina Koch the only woman, Canadian Space Agency astronaut Jeremy Hansen the only person not from the United States, and Reid Wiseman the oldest person to travel beyond low Earth orbit and around the Moon. During their lunar flyby, the crew broke Apollo 13's record of 248,655 miles (400,171 km) for the greatest human distance from Earth, reaching a maximum distance of 252,756 miles (406,771 km). After its launch, Artemis II gained widespread global attention for its achievements and inclusive crew, giving rise to the term "Moon joy".
Mission planning and launch date selection (2017–2021)
In 2017, Exploration Mission-2 was planned as a single-launch flight of a Space Launch System (SLS) Block 1B rocket equipped with the Exploration Upper Stage, carrying a lunar Block 1 Orion spacecraft, and a payload capacity of 50.7 tonnes (112,000 lb). The mission concept involved rendezvousing with an asteroid that would have been placed in lunar orbit by the robotic Asteroid Redirect Mission, allowing astronauts to conduct spacewalks and collect samples.
After the Asteroid Redirect Mission was cancelled in April 2017, NASA proposed an alternative mission involving an eight‑day free-return trajectory around the Moon with a crew of four astronauts.
Another 2017 proposal suggested sending four astronauts aboard Orion on an 8‑ to 21‑day lunar mission to deliver the first element of the planned Lunar Gateway space station. This proposal did not come to fruition, and in March 2018, NASA decided that the Gateway's initial module would instead launch on a commercial rocket due to delays in constructing the Mobile Launcher required for the more powerful Exploration Upper Stage. The SpaceX Falcon Heavy was selected as the launch vehicle. However, the Lunar Gateway program was cancelled in March 2026.
Hardware development, testing and integration (2021–2025)
On February 11, 2023, NASA rotated the Artemis II core stage's engine section to a horizontal position, marking the final major milestone before integration with the rest of the vehicle. On March 20, the engine section was mated with the core stage in Building 103 at the Michoud Assembly Facility in New Orleans, Louisiana. In March 2023, NASA initially expected to deliver the completed core stage to the Kennedy Space Center (KSC) that summer, but by May, the timeline had shifted to late autumn 2023.
The four RS-25 engines (serial numbers E2047, E2059, E2062, and E2063) were installed on the core stage by September 25, 2023. After a leak was discovered in the oxygen‑valve hydraulics, engine E2063 was replaced with E2061 in April 2025.
The fully outfitted core stage was delivered to KSC between July 16 and 25, 2024. The adapters required for integration of the full launch vehicle reached substantial completion in June 2024 and arrived at KSC in September 2024.
The Artemis II crew was announced on April 3, 2023, by NASA administrator Bill Nelson during his "State of NASA" address at a NASA facility at Ellington Field outside Houston, Texas. The crew made a public appearance that evening at the nearby NRG Stadium during the 2023 March Madness basketball championship game.
NASA had originally targeted September 2024 to begin rocket-stacking operations. However, the schedule was delayed by more than two months due to investigations into issues with Orion's life-support system and unexpected heat shield damage observed after the Artemis I reentry. Rocket stacking began on November 20, 2024. Stacking was completed on October 20, 2025, with the installation of the fully integrated Orion spacecraft, ESM, and launch abort system atop the SLS rocket.
After the uncrewed Artemis I mission in November 2022, NASA engineers identified unexpected erosion of the Orion spacecraft's ablative heat shield following atmospheric reentry. Post-flight inspections found areas of char loss in the AVCOAT ablative heat shield material, in which portions of the material eroded more extensively than predicted by preflight models. NASA reported that temperatures inside the crew module remained within design limits, but the unanticipated behavior of the material prompted further investigation. Close-up imagery of the damage was not publicly released until May 2024, when it appeared in a report issued by the NASA Office of Inspector General.
In April 2024, NASA established an independent review team to assess heat shield performance and the agency's proposed approach for the Artemis II mission. The review concluded in December 2024, after which NASA announced that it would proceed with Artemis II using the existing heat shield. NASA held a press briefing to outline its findings, but the publicly released version of the review team's report was heavily redacted, prompting criticism from some former NASA engineers and astronauts regarding the level of transparency.
NASA engineers determined that the char loss observed during Artemis I was caused by hot gases becoming trapped within the AVCOAT material, leading to spalling, cracking and increased localized material loss during reentry. Rather than replacing the heat shield for Artemis II, NASA modified the reentry trajectory by increasing the descent angle, reducing the time the spacecraft would spend in the thermal environment associated with the damage. According to NASA, modeling and ground testing indicated that this change would limit further char loss while remaining within Orion's structural and thermal margins.
As part of the certification process for Artemis II, NASA conducted additional testing and analysis, including evaluations of scenarios involving more extensive heat-shield damage. NASA stated that these analyses showed the underlying structure of the Orion capsule would remain intact and capable of protecting the crew under conditions exceeding those expected during the mission's reentry.
In January 2026, NASA administrator Jared Isaacman stated that he supported proceeding with Artemis II using the existing heat shield after reviewing the agency's analysis and meeting with engineers and outside experts. Some participants who had previously expressed concerns indicated that the additional data addressed their questions, while others continued to object to flying the mission without a redesigned heat shield. NASA has stated that design changes addressing AVCOAT permeability are planned for the heat shield intended for Artemis III.