April 4, 2026

A closer look at Artemis I, the uncrewed test flight that opened the program in 2022.

The vehicle

Orion CM-002 flew with the European Service Module ESM-1 (built by Airbus). The ESM provides propulsion, power, thermal control, and consumables. It is a direct derivative of the ATV cargo vehicle that ESA flew to the ISS. The SLS core stage uses four RS-25 engines, the same engines that flew on the Space Shuttle, refurbished and modified for expendable use.

The flight

Launch: November 16, 2022, 06:47 UTC, from LC-39B at Kennedy Space Center. Splashdown: December 11, 2022, off the coast of Baja California.

Total duration: 25 days, 10 hours, 52 minutes.

The trajectory went translunar, with a first close lunar flyby on November 21 at 130 km altitude, then insertion into a Distant Retrograde Orbit (DRO) — a highly stable orbit far from the Moon used specifically because no propulsion is needed to maintain it. Orion stayed in DRO for six days (November 25–30), reaching a maximum distance from Earth of 432,210 km on November 28, breaking the record previously held by Apollo 13. A second flyby at 128 km on December 5 sent Orion back toward Earth.

Total distance traveled: approximately 2.1 million km.

“The passengers”

No human crew, but three test subjects:

• Commander Moonikin Campos: a suited mannequin torso in the commander seat, instrumented with two radiation dosimeters to measure what a crewmember would experience during the mission. Named after Arturo Campos, an electrical engineer who played a key role in the Apollo 13 rescue.
• Helga and Zohar: two phantom torsos made of materials that simulate human tissue, placed in the rear seats as part of the MARE (Matroshka AstroRad Radiation Experiment). Zohar wore the AstroRad radiation protection vest, Helga did not — the comparison gives data on how much the vest reduces dose.

Problems

The road to launch had two scrubbed attempts: August 29 (engine 3 temperature sensor reading above the allowed limit, because of a faulty sensor) and September 3 (hydrogen leak at the tail service mast). The actual launch in November went cleanly.

During reentry, there was unexpected loss of material from the AVCOAT ablative heat shield. The effect was more than anticipated, though it did not compromise the mission. NASA has been investigating the root cause before flying crew on Artemis II.

What it validated

The full stack had never flown together before this test: SLS, Orion, ground systems, mission operations.

Artemis I confirmed the structural and thermal performance of Orion during a high-speed reentry from lunar distance (approximately 11 km/s), the performance of the ESM, and the communication and navigation systems.

The data from Campos, Helga, and Zohar feeds directly into crew safety planning for subsequent missions.

See: NASA Artemis I