Artemis 2 Mission: Lunar Progress and Korean Satellite Communication Failure

South Korea’s first attempt to receive signals from beyond geostationary orbit has faced a critical setback. K-RadCube, a nanosatellite deployed during NASA’s Artemis II mission, has failed to establish normal communication with ground stations, leaving its mission success in doubt.

The Korea Aerospace Administration (KASA) and the Korea Astronomy and Space Science Institute (KASI) announced on April 3, 2026, that while some signals were detected during initial operation attempts, the satellite has not achieved the stable communication required to transmit observation data.

Deployment and Initial Communication Attempts

K-RadCube was launched as part of the Artemis II mission on the morning of November 2, 2025. It was deployed from the Orion spacecraft at 12:58 p.m. Korean time that same day, at an altitude of approximately 40,000 kilometers.

Following deployment, KASA utilized overseas ground station antennas to attempt contact. A weak signal was first detected by the Maspalomas ground station in Spain around 2:30 p.m. On November 2, 2025.

Later that evening, at 9:57 p.m., a ground station in Hawaii received telemetry data from the satellite. At the time of this reception, K-RadCube was approximately 68,000 to 68,800 kilometers away from Earth. This distance represents the farthest signal reception ever achieved by a Korean CubeSat, surpassed only by the Danuri lunar orbiter, which communicated from 1.5 million kilometers in 2022.

Technical Challenges and Orbital Risks

Despite these initial signals, the telemetry data received in Hawaii was described as abnormal. The primary technical concern now centers on the satellite’s orbit and its ability to maintain altitude.

K-RadCube was placed into an orbit with an apogee—the farthest point from Earth—of 70,000 kilometers and a perigee—the closest point—of 0 kilometers. To avoid atmospheric reentry, the satellite was required to perform a perigee-raising maneuver.

KASA and KASI have stated that it is currently unconfirmed whether this maneuver was successful. If the satellite failed to raise its perigee altitude, it will eventually re-enter Earth’s atmosphere and burn up.

Operational Outlook

KASI, in cooperation with operating partners Naraspace and KT SAT, planned to continue initial operations until 12:30 p.m. On April 4, 2026. This window was intended to determine if the satellite remained viable and if normal communication could be restored.

Kang Kyung-in, head of KASA’s Space Science and Exploration Division, noted that the project represents the first Korean case of receiving a signal from beyond geostationary orbit, underscoring the technical ambition of the mission despite the current communication failures.

The failure of K-RadCube to establish a stable link means that the primary objective of transmitting scientific observation data remains unfulfilled. Analysis suggests a low probability of the satellite’s survival if the orbital maneuvers were not executed correctly.