All 5 NeonSat cluster satellites establish contact with ground stations after Nuri launch

All five ultra-small cluster satellites — known as NeonSat — launched aboard South Korea's homegrown Nuri rocket have successfully established initial contact with ground stations. It marks the first time the country has simultaneously launched five mass-produced national satellites on the same mission and achieved contact with all of them.

Korea AeroSpace Administration (KASA) and KAIST announced Wednesday that NeonSat units 2 through 6, placed into orbit by Nuri's fifth launch, had completed two-way communications with ground stations at the Korea Aerospace Research Institute in Daejeon, the Sejong Antarctic base and the Svalbard Arctic station — all by 6 p.m. that day.

The first to respond was unit 6, which established contact with the Antarctic Sejong base at 1:08 p.m. Unit 4 followed at 2:42 p.m. via the Sejong base, unit 3 at 3:27 p.m. via Svalbard, and unit 2 at 4:18 p.m. via the Sejong base. The last to check in, unit 5, completed two-way contact with the Sejong base at 5:52 p.m.

Initial contact confirmed that all five satellites transmitted their unique identification data and telemetry readings normally and responded correctly to commands from the ground. Solar panel deployment, power generation, temperature and attitude control were all found to be in generally good condition.

KASA and KAIST said they have determined that all five satellites reached their target orbits successfully and have begun full-scale initial operations.

Engineers will now conduct detailed checks of each satellite's body, optical payload, and communications and attitude-control systems, and will capture and receive test imagery. Once in-orbit testing and image quality verification are complete, the satellites will join existing ones in a constellation Earth-observation mission.

The achievement carries broader significance as it demonstrates South Korea's ability to operate a satellite constellation in practice, not merely to manufacture multiple satellites. Engineers successfully identified the individual orbits of each satellite and completed separate contact and status checks for all of them within the limited communication windows available from ground stations.

The ultra-small cluster satellite project is led by KAIST's Satellite Technology Research Center, with the Korea Aerospace Research Institute, Satrec Initiative and other domestic industry and academic partners involved. The program covers not only the satellites themselves but also the command-and-control ground systems needed to operate multiple satellites simultaneously, along with image calibration and utilization systems.

Most of the secondary satellites carried aboard Nuri also made contact. Eight of the nine secondary cubesats — the domestic-component space-verification platform unit 2, Sledge, GBSat, Ulysses, SD1Sat, B-1012, Jack-007 and CPSat — completed communications with ground stations. Contact attempts with Daejeon Sat 1 are ongoing.

KASA Administrator Oh Tae-seok said the simultaneous launch of five national satellites and successful initial contact with all of them confirmed South Korea's capacity for satellite mass production and constellation operations. "We will carry out follow-on initial operations and performance verification without delay, and put these satellites to practical use for national security and disaster response," he said.