Nuri Rocket Set for Fifth Flight With Record 15-Satellite Mission

South Korea is preparing to launch its homegrown Nuri rocket for a fifth time on Wednesday, with the mission set to carry 15 satellites into orbit and begin building the country’s first domestically launched microsatellite constellation.

The three-stage rocket is scheduled to lift off at 12:25 p.m. from the Naro Space Center in Goheung, around 400 kilometers south of Seoul. Oh Tae-seok, administrator of the Korea AeroSpace Administration, said the vehicle was technically ready and that weather and space conditions were favorable. Officials had also found no concern about a potential collision with objects already in orbit.

The payload comprises five New-space Earth Observation Satellite Constellation for National Safety spacecraft, known as NEONSATs, and 10 smaller CubeSats. The flight will be Nuri’s first attempt to deploy several primary satellites designed to carry out the same mission, adding a new level of operational complexity to South Korea’s launch program.

After liftoff, the rocket’s first and second stages are expected to separate about 123 seconds and 268 seconds into the flight. Satellite deployment is planned between 810 and 960 seconds after launch at an altitude of roughly 575 kilometers.

The five NEONSAT spacecraft, numbered two through six, will separate one at a time at intervals of 35 to 40 seconds. Nuri’s upper stage will rotate by about 45 degrees between releases to reduce the risk of collision. The 10 CubeSats will then be released two at a time at 10-second intervals. Once every satellite has been deployed, the rocket will carry out a collision-avoidance maneuver and vent its remaining fuel, bringing the active flight sequence to an end about 20 minutes after liftoff.

Each NEONSAT weighs less than 100 kilograms and carries an electro-optical camera. The instruments are designed to distinguish objects as small as one meter in black-and-white imagery and four meters in color. The satellites will observe the Korean Peninsula and nearby areas for national security and disaster-response purposes.

South Korea plans to complete the 10-satellite constellation by sending five more NEONSATs into orbit on Nuri’s sixth flight next year. Once fully operational, the network is expected to image the peninsula more than three times per day and revisit the same location within 24 hours. The Korea Aerospace Research Institute will monitor Wednesday’s flight from tracking facilities in South Korea and Palau in the western Pacific.