The Korean space launch vehicle Nuri is soaring into space, spouting flames from the launch pad of the Naro Space Center in Goheung, Jeollanam-do, at 4 pm on the 21st. /Goheung=Photo Foundation
The space rocket Nuri, developed by Korea with its own technology, was successfully launched on the 21st, carrying five satellites. After the US, Russia, China, Japan, the European Union (EU) and India, Korea has risen to the top of the list of ‘world’s seven largest space powers’ that have launched practical satellites of more than 1 ton on their own.
The Nuri flew into space from the launch pad dedicated to the Naro Space Center in Goheung, Jeollanam-do at 4 pm that day. She had to stand up the day before, and after her breath-taking preparations since 7 am, Nuri-ho finished injecting her fuel (kerosene) at 2:27 pm. With the end of the countdown (automatic operation before launch), which started 10 minutes before launch, the Nuri soared with a roaring sound by receiving the power of 3500 degrees high-temperature and high-pressure gas emitted from the first stage.
The first stage of the Nuri rocket was separated at an altitude of 62 km, 123 seconds after launch. Then, at a point 202 km away, the fairing, the cover covering the satellite, was successfully removed. 269 seconds later, at an altitude of 273 km, the second stage was separated. At 4:14:34 p.m., when the speed reached Mach 22 (7.5 km/s), at an altitude of 700 km, the performance verification satellite carrying four micro-satellites was separated from the third stage and put into orbit. At 42 minutes after launch, this satellite first communicated with the Antarctic Sejong Base and announced that it was ‘safe’.
Nuri is a native launch vehicle developed in 2010 by the Ministry of Science and ICT and the Korea Aerospace Research Institute to put a 1.5-ton practical satellite into low orbit (600-800 km). So far, 1.9572 trillion won has been invested. The sweat of 300 domestic companies such as Hanwha Aerospace, Korea Aerospace Industries (KAI), and Hyundai Heavy Industries is melted.
President Yoon Seok-yeol said, “The success of the Nuri launch is the product of the challenges of the past 30 years.
“The target trajectory has been reached,” the researchers shout… Communication with the satellite 42 minutes after launch
At the Space Launch Observatory in Goheung, Jeollanam-do, on the 21st, visitors cheer as they watch the launch of the Korean-style space rocket Nuri. /yunhap news
On the morning of the 21st, the Naro Space Center in Goheung, Jeollanam-do. Maritime control of a width of 24 km and a length of 78 km has begun. The maximum wind speed was only 4 m/s. Although the rainy season front has developed in the sea south of Jeju, it has been confirmed that lightning will not occur up to an altitude of 30 km off the coast of Oe Narodo, where the Naro Space Center is located.
1 hour before launch. The final inspection of the launch operation has begun. The electronic payload (Evionix) that guides the Nuri into space is turned on. The fuel kerosene (kerosene) and oxidizer (liquid oxygen) have been filled in the 48m high umbilical tower surrounding Lake Nuri. The level sensor of the first stage oxidizer tank replaced earlier was not abnormal. The projectile standing device was withdrawn and the alignment of the inertial navigation guidance system started. Soon after, the countdown began.
○Historical launch moment
At 4 pm, Lake Nuri soared with a roar. The flue gas temperature is 3500 degrees Celsius. It is more than double the temperature of POSCO’s furnace for melting molten iron (1500 degrees). The pressure soared to 60 times atmospheric pressure (60 bar). To cool the launch pad, 1.8 tons of coolant flowed continuously per second.
The moment Nuri floats in the air, four 75-ton engines are tied and the direction control (gimbaling) technology that produces uniform thrust is activated. Dozens of researchers and reporters at the site confirmed in a bright flash that the first stage projectile manufacturing technology was completed by our own hands. The learning effect that had undergone nearly 200 repeated tests with 33 75-ton engines before the launch on that day shone in real life.
123 seconds after launch, the first stage was separated at an altitude of 62 km at a speed of 1.8 km per second. It is more than 7 times the speed of a regular passenger plane (250 m/s). The amount of oxidizer and fuel used per second during the combustion of the first stage engine is over 1 ton.
At an altitude of 202 km (227 seconds after launch), the satellite cover (pairing) was removed. The reason for separating the fairing before separating the second and third stages is to reduce the weight of the projectile. At an altitude of 273 km, the second stage separated at a speed of 4.4 km/s. Stages 1–2 and 2–3 interstages equipped with explosives exploded without a hitch, and stage separation was achieved. The 3rd stage carrying the performance verification satellite and 4 cube satellites flew alone and started accelerating. At 4:14:34 pm, the performance verification satellite was separated from the third stage. The broadcast from the control center was mixed with shouts and applause from the researchers. The research team, dressed in matching pale pink T-shirts, hugged his colleagues and took a commemorative photo with the control screen in the background.
○Indigenous rocket with satellite orbit
The eyes of the officials of the Korea Aerospace Research Institute did not fall from the number on the control screen of the Naro Space Center for even an hour. Finally, the target three-stage combustion time was met. It reached an altitude of 700 km and a speed of 7.5 km/s. Cheers erupted from everywhere. After the failure of the first Nuri launch in October of last year, the frustration and irritability that had accumulated for eight months disappeared in an instant.
For this launch, all advanced equipment at the Naro Space Center, Jeju Island, and Palau, a Pacific island nation, was mobilized. A tracking radar that can track a projectile up to a radius of 3000 km and obtain real-time location information, and a remote data receiving device (telemetry) that can check the flight trajectory and operation status of a projectile up to 2000 km were operated. 42 minutes and 23 seconds after launch. The data sent by the satellite was received at the Sejong Base in Antarctica.
The performance verification satellite, which has been placed in orbit, performs a ‘first pointing’ process that takes a position and aligns it toward the sun for 4 hours after launch. It is a preliminary work to stably orbit and generate electricity through solar panels. The test operation of the major equipment aboard the performance verification satellite is completed by the seventh day after being put into orbit.
○Joined as one of the world’s 7 largest space powers
With the success of the Nuri spacecraft, Korea has joined the space power of ‘G7’, which can launch more than 1 ton of practical satellites. Currently, six countries capable of launching magnetic satellites are Russia, the United States, the European Union (EU), China, Japan, and India. Israel, Iran, and North Korea are also capable of self-launching, but are known to stay under 300 kg.
Regarding the success of the second launch of the Nuri, Hwang Jin-young, a senior researcher at the Korea Aerospace Research Institute, said, “20 years after we first started developing a Korean launch vehicle in 2002, we have fully equipped our own space exploration capabilities.” The first step was also successfully completed.”
Lee Hae-seong/Goheung = Reporter Kim Jin-won ihs@hankyung.com
