South Korea’s space agency said Tuesday that the country’s 15-story-tall Nuri launcher successfully reached orbit for the first time, giving the nation a fully domestic satellite launch capability after a $1.5 billion development program lasting more than a decade.
The Nuri rocket lifted off from the Naro Space Center, on an island nearly 300 miles (500 kilometers) south of Seoul, at 3 a.m. EDT (0700 GMT) Tuesday with a small technology demonstration spacecraft, four university-built CubeSats, and a satellite mock-up to mimic the weight of a primary payload.
The Korea Aerospace Research Institute, or KARI, said the Nuri rocket soared into an orbit about 435 miles (700 kilometers) above Earth, and the test satellites were “accurately separated” from the launcher. KARI is South Korea’s government space agency.
President Yoon Seok-youl declared “the road to space from Korean land has been opened” in a congratulatory statement to the Nuri rocket team. Yoon watched the launch from his office via a direct video connection.
“Now, the dreams and hopes of the Korean people and young people will extend into space,” the South Korean president said.
The Nuri rocket is a medium-class launcher standing nearly 155 feet (47.2 meters) tall and measuring around 11.5 feet (3.5 meters) in diameter. The Nuri, which means “world” in Korean, is designed to place a payload of up to 3,300 pounds (1,500 kilograms) into an orbit more than 372 miles (600 kilometers) in altitude.
The rocket program is part of a period of growth in South Korea’s space program, which has long produced Earth observation and technology demonstration satellites. Now the country has a rocket to launch its own satellites, and South Korean engineers are finishing work on a lunar science probe to launch from the United States later this year.
The first test flight of the Nuri rocket last October failed just before reaching orbit. Investigators determined a helium tank fell off its anchor inside the oxidizer tank on the rocket’s third stage, causing damage and leading to the premature cutoff of the third stage engine about 46 seconds before the planned shutdown time.
The helium tank holds pressurant for the upper stage. Engineers stiffened the support structure for the helium tank on the next Nuri rocket, and no such problems were detected during Tuesday’s successful flight.
“The Korea Aerospace Research Institute will not be complacent with the success of the Nuri, and will continue to strive towards the space power of the Republic of Korea,” KARI said in a statement.
The launch team at the Naro Space Center loaded kerosene and liquid oxygen propellants into the three-stage rocket a few hours before liftoff. After a smooth terminal countdown, four KRE-075 engines ignited with more than 600,000 pounds of thrust to propel the Nuri launcher off the seaside launch pad.
The rocket arced downrange south from the Naro Space Center, and exceeded the speed of sound in less than a minute. A tracking camera view streamed live on YouTube by South Korea’s science ministry showed the rocket soaring into a clear sky over the Korean coastline, where liftoff occurred at 4 p.m. local time.
Two minutes after launch, the first stage’s four engines shut down. The booster jettisoned moments later, and a single KRE-075 engine on the Nuri’s second stage ignited to continue the climb into space. The live video continued tracking the rocket into the second stage burn.
The rocket’s payload fairing, or nose cone, jettisoned as planned nearly four minutes into the flight, officials said. And the rocket’s third stage, powered by a smaller KRE-007 engine, ignited to accelerate to an orbital velocity near 17,000 mph, or about 7.5 kilometers per second.
A 358-pound (162.5-kilogram) technology verification satellite, named PVSAT, deployed from the Nuri rocket’s third stage about 15 minutes after launch. About one minute later, a nearly 2,900-pound (1.3-metric ton) satellite mock-up separated from the rocket. The dummy satellite simulated the mass of a larger primary payload that could ride on future Nuri missions.
The video highlights reel posted below shows views of the major launch events from cameras on-board the rocket, including liftoff, staging, and separation of PVSAT and the satellite mock-up.
Four CubeSats were stored on the PVSAT spacecraft for deployment later. The largest of the CubeSats was the 21.2-pound (9.6-kilogram) STEP Cube Lab 2 satellite from Chosun University, with a suite of miniaturized electro-optical mid-infrared and loogwave infrared Earth observation cameras.
The SNUGLITE 2 nanosatellite, from Seoul National University, will demonstrate GPS radio occultation measurements using attenuation of satellite navigation signals to gather data on Earth’s atmosphere. The MIMAN CubeSat was developed at Yonsei University, and carries an instrument for atmospheric dust monitoring.
The fourth CubeSat on the Nuri launch was RANDEV, which hosts a hyperspectral camera to image volcanoes, coastal regions, and clouds. RANDEV was developed at the Korea Advanced Institute of Science and Technology.
The Nuri rocket program is a follow-up to the Naro 1 rocket developed in a partnership between Russia and South Korea.
The first two Naro 1 rockets failed in 2009 and 2010, but the third Naro 1 mission in 2013 successfully deployed a small South Korean technology demonstration satellite, making South Korea the 11th country to launch its own satellite into orbit, but the feat was not accomplished without international help.
Russia’s space contractor Khrunichev developed the Naro 1’s first stage, and the booster’s kerosene-fueled RD-151 main engine was built by NPO Energomash, another Russian company. Russia and South Korea ended the Naro 1 program after the 2013 test flight.
Korea Aerospace Industries led the South Korean industrial team responsible for developing the Nuri rocket.
The rocket’s KRE-075 engines, developed by the South Korean company Hanwha Aerospace, each use a gas generator to drive a pump feeding propellant into the thrust chamber. SpaceX’s Merlin engines, which power the Falcon 9 rocket, use a similar design.
More than 300 South Korean companies have participated in the Nuri rocket program.
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