Six of 8 satellites successfully separate from space rocket Nuri

Six out of the total of eight satellites separated from Korea's domestically developed space rocket Nuri, successfully entered their target orbits and are sending signals.

The Korea Space Launch Vehicle (KSLV-II), or Nuri, lifts off from the launch pad at the Naro Space Center in Goheung County, South Jeolla Province, at 6:24 p.m. on Thursday. [KOREA AEROSPACE RESEARCH INSTITUTE]

Six out of the total of eight satellites separated from Korea's domestically developed space rocket Nuri, successfully entered their target orbits and are sending signals. Meanwhile, attempted communication with the remaining two satellites are “still ongoing.”

The main payload, Next Generation Small Satellite, or NEXTSat-2, successfully deployed a 5.2-meter antenna after entering its target orbit and making two-way communication, the Ministry of Science and ICT confirmed Friday.

The King Sejong Station, a research station for the Korea Antarctic Research Program situated on the Barton Peninsula, first received a signal from the satellite at 7:07 p.m. from KAIST’s Satellite Technology Research Center (Satrec) in Daejeon. Then the center succeeded in sending a signal back to the satellite at 7:58 p.m.

"After deploying the antenna, we inspected the components and satellite's control function," the Science Ministry said. “The satellite’s functionality in communication, data processing and solar panels are all in working order.”

The 179.9-kilogram NEXTSat-2, developed by the KAIST's Satrec, is equipped with a small-sized synthetic aperture radar that can capture high-resolution images regardless of weather conditions.

After a week-long examination, NEXTSat-2 will undergo test operations for three months and then carry out its mission, including monitoring the cosmic radiation in low earth orbit. The satellite will circle Earth 15 times each day for two years.

The ministry is still attempting to make contact with one of the four CubeSats developed by Korea Astronomy & Space Science Institute, codenamed SNIPE.

For the rest of three CubeSats developed by private companies, the ministry confirmed to have received signals from Lumir’s Lumir-T1 at 7:53 p.m. and Cairo Space’s KSAT3U at 11:07 p.m. The ministry is still “attempting” to make contact with the remaining CubeSat by Justek.

Cho Sun-hak, the head of space policy and nuclear energy bureau at the Ministry of Science and ICT, speaks at a press briefing on Friday at the government complex in Sejong to explain about communicative process of eight satellites launched from the Nuri rocket. [NEWS1]

“The size of the CubeSat is small, and there are limits to its functions compared to other satellites, so when we decided to launch them out to space, it is true that we did have some doubt,” said Cho Sun-hak, the ministry’s head of space policy and nuclear energy bureau.

However, Cho emphasized that the “communicative process is not complete” and it is still early to determine full success or failure of some of the satellites’ operations.

Starting at 6:24 p.m. Thursday, Nuri completed its 1,138-seconds-long journey to space. Initially set to launch at that same time on Wednesday, it was canceled two hours before the planned liftoff due to a communication glitch in its launch system.

The third test launch was the domestic rocket’s first attempt at deploying multiple satellites with the vehicle.

In the second launch last June, Nuri carried a 1,500-kilogram payload, including a performance verification satellite, four CubeSats and a dummy payload. The CubeSats were placed inside the performance verification satellite during the second launch.

The latest liftoff took place more than two hours later than last June’s launch with an aim to bring NEXTSat-2, its main payload, into the targeted orbit which could only be done at sunset when the satellite can face the sun and secure enough solar energy to power its radar for the mission.

It’s also the first time a private company participated in the launch operation for a public-private technology transfer.

Hanwha Aerospace signed a 286-billion-won ($217 million) contract with Korea Aerospace Research Institute to run the Korea Space Launch Vehicle Advancement Program. The Korea Space Launch Vehicle Advancement Program aims to improve the Nuri rocket through repeated launches with an estimated budget of 687.4 billion won through 2027.

Three more launches are scheduled until 2027.

BY LEE JAE-LIM, SARAH CHEA [lee.jaelim@joongang.co.kr]