LOS ANGELES -- NASA on Thursday announced delays in its Artemis moon exploration program following a technical problem identified in its Orion spacecraft.

NASA is now targeting April 2026 for Artemis II, its first crewed moon mission, and mid-2027 for Artemis III, a historic moon landing mission exploring the lunar South Pole region.

Artemis III will be the first mission to return U.S. astronauts to the surface of the moon in more than 50 years.

The agency previously set September 2025 for Artemis II, and September 2026 for Artemis III.

The delay came after NASA concluded the examination of a technical problem happened during the agency's Artemis I mission in 2022.

The Artemis I flight test, carrying the Orion spacecraft, was launched on Nov. 16, 2022, from NASA's Kennedy Space Center in Florida. The Artemis I mission was the first integrated flight test of the agency's deep space exploration systems: the Orion spacecraft, the Space Launch System (SLS) rocket, and ground systems.

During the Artemis I mission, the Orion spacecraft experienced an unexpected char loss across its heat shield, according to NASA.

Extensive analysis, including from more than 100 tests at unique facilities across the country, determined the heat shield on Artemis I did not allow for enough of the gases generated inside a material called Avcoat to escape, which caused some of the material to crack and break off.

Avcoat is designed to wear away as it heats up and is a key material in the thermal protection system that guards Orion and its crew from the nearly 5,000 degrees Fahrenheit of temperatures that are generated when Orion returns from the moon through Earth's atmosphere, according to NASA.

Approximately 200 Avcoat samples were removed from the Artemis I heat shield at NASA's Marshall Space Flight Center in Alabama for analysis and inspection.

"We took our heat shield investigation process extremely seriously with crew safety as the driving force behind the investigation," said Howard Hu, manager of Orion Program, NASA's Johnson Space Center in Houston. "The process was extensive. We gave the team the time needed to investigate every possible cause, and they worked tirelessly to ensure we understood the phenomenon and the necessary steps to mitigate this issue for future missions."

Engineers already are assembling and integrating the Orion spacecraft for Artemis III based on lessons learned from Artemis I and implementing enhancements to how heat shields for crewed returns from lunar landing missions are manufactured, to achieve uniformity and consistent permeability, according to NASA.

The Orion spacecraft, built by NASA and prime contractor Lockheed Martin, is currently the only spacecraft capable of crewed deep space flight and high-speed return to Earth from the vicinity of the moon.

On NASA's Artemis moon exploration missions, Orion will carry the crew to space, provide emergency abort capability, sustain the crew during space travel, and provide safe re-entry from deep space return velocities.

With the Artemis campaign, NASA plans to land the first woman, first person of color, and its first international partner astronaut on the moon, and establish long-term exploration for scientific discovery and preparation for human missions to Mars.