Nine CubeSats deployed by Nuri’s fifth launch vehicle have all sent signals back to Earth.
The Korea AeroSpace Administration (KASA) and the Korea Aerospace Research Institute (KARI) said on the 13th that ground stations had successfully received signals or data from all nine secondary payload satellites that were successfully separated after Nuri’s fifth launch on the 7th.
Six of the satellites have completed two-way communications, sending and receiving commands and data. One of the 10 satellites did not separate from the launch vehicle.
◆ Five made contact on launch day, and one the following day
The six satellites to complete two-way communications are SpaceLintec’s B-1012; KARI’s second space verification platform for domestically developed components and parts; the Unmanned Exploration Research Institute’s Ulysses; Space&Bean’s SD1Sat; Chosun University’s Space Optical Communication Orbit Verification Satellite; and Daejeon Metropolitan City’s DaejeonSat-1.
All but DaejeonSat-1 completed two-way communications during their first contact attempts on launch day. The Chosun University satellite also collected operational and image data. DaejeonSat-1 made contact the following day, on the 8th, confirming that its solar panels had deployed. The six satellites are checking the status of their buses and payloads or collecting operational data.
O&B Space’s Sledge, Cosmoworks’ Jack-007, and KAIST’s G-BSAT have successfully downlinked data from the satellites to ground stations. Sledge and G-BSAT are attempting uplinks, sending commands from the ground to the satellites. Successful uplinks would establish two-way communications. Each satellite will begin its main mission after checking that its systems are operating properly during initial operations.
◆ One satellite never separated
Nuri’s fifth launch vehicle lifted off at 12:25 p.m. on the 7th from the Naro Space Center in Goheung, South Jeolla Province. It was South Korea’s first clustered launch, placing 15 satellites—a five-satellite cluster of microsatellites, Nos. 2 through 6, and 10 CubeSats—into a sun-synchronous orbit at an altitude of about 570 kilometers.
The five cluster satellites were successfully deployed one at a time at intervals of 30 to 40 seconds. About 43 minutes after launch, Satellite No. 6 made first contact with the King Sejong Station in Antarctica. The CubeSats were deployed two at a time.
Only PerSat, made by Quaternion, failed to emerge. According to KARI, the deployment signal was sent successfully, but the satellite did not separate from the launch vehicle. The cause has not yet been announced. The fifth launch was the first to use a low-shock separation system designed to reduce the impact on satellites during deployment to levels specified by international standards.
◆ Contact on launch day for the fifth launch, compared with nine days for the fourth
KASA Administrator Oh Tae-seok said, “With Nuri’s fifth launch, we succeeded in making contact with the CubeSats in a much shorter time than after the fourth launch. This signifies a higher level of technical maturity, and we will continue to strengthen our space transportation capabilities.”
The fourth launch, used for comparison, took place on November 27 last year. It placed the Next-Generation Mid-sized Satellite 3 and 12 CubeSats into an orbit about 600 kilometers high, and all 12 eventually made contact.
However, three of the satellites had not established two-way communications by the time of a briefing five days after launch. Contact with those three was confirmed between December 4 and 6, seven to nine days after launch.
In the fifth launch, five of the nine deployed CubeSats completed two-way communications on launch day. KASA said that faster contact indicates the launch vehicle placed the satellites more accurately in their target orbits and provided more precise location information.
The fifth launch is an intermediate step in transferring Nuri operations to the private sector. Hanwha Aerospace, the system integration company, took the lead in manufacturing and assembly, and 23 of its personnel also took part in launch operations. After the sixth and seventh launches, Hanwha will operate launches independently. The sixth launch, scheduled for next year, will carry five more microsatellites for the cluster.