SEOUL, May 25 (Yonhap) -- The following are fast facts about South Korea's homegrown space rocket Nuri, or the Korea Space Launch Vehicle-II (KSLV-II), which was launched from Naro Space Center in the country's southern coastal town of Goheung.
-- Nuri means "world" in Korean and is the name of the Korea Space Launch Vehicle-II (KSLV-II) rocket. Nuri is a three-stage rocket developed to put satellites into low orbit 600-800 kilometers above Earth.
-- The 47.2-meter-long, 200-ton Nuri rocket has a maximum diameter of 3.5 meters and uses four 75-ton liquid thrust engines in the first stage, a 75-ton liquid engine in the second stage and a 7-ton liquid engine in the third stage.
-- The first launch in October 2021 ended in partial success. Nuri successfully flew to a target altitude of 700 kilometers but failed to put a 1.5-ton dummy satellite into orbit as its third-stage engine burned out earlier than expected. A probe revealed the helium tank in the third-stage rocket fell off due to increased buoyancy during the flight and eventually caused the engine to shut off prematurely.
-- Following the first launch, Nuri underwent the reinforcement of an anchoring device of the helium tank inside the third-stage oxidizer tank.
-- On the second attempt in June 2022, Nuri successfully completed its flight sequence and deployed satellites at the target altitude of 700 kilometers as planned. Nuri carried a 180-kilogram performance verification satellite meant to test the rocket's capabilities, and four cube satellites developed by four universities for academic research purposes, along with a 1.3-ton dummy satellite.
-- The second launch has made South Korea the seventh country in the world to have developed a space launch vehicle that can carry satellites weighing over 1 ton, following Russia, the United States, France, China, Japan and India.
-- The third launch will take place Wednesday. Nuri will carry a 180-kilogram next-generation small satellite named NEXTSAT-2, developed by the Korea Advanced Institute of Science and Technology, and seven cube satellites, including four microsatellites, codenamed SNIPE, developed by the Korea Astronomy and Space Science Institute.
-- It is the first time that Nuri is tasked with handling separate multiple satellites in one flight.
-- The launch site is Naro Space Center in Goheung, 328 kilometers south of Seoul.
-- Nuri is designed to fly southward from the launch site on the southern coast. The first stage is expected to fall 430 km away from the launch site and the second stage in the sea 2,804 km away from the launch site.
-- Its planned flight sequence shows the first stage separation will take place 125 seconds after the launch at an altitude of 64.5 km, with the fairing separation to come at 234 seconds at an altitude of 204 km. Then, the second stage separation will occur at 272 seconds at 258 km high. NEXTSAT-2 will be separated at 783 seconds and the seven cube satellites at 803 seconds, 823 seconds, 843 seconds, 863 seconds, 883 seconds, 903 seconds and 923 seconds, respectively, at an altitude of 550 km. The flight will end at 1,138 seconds.
-- South Korea has invested 2 trillion won (US$1.5 billion) since 2010 in the project. More than 300 domestic companies have taken part, including Hanwha Aerospace Co. that took charge of assembling the 75-ton liquid propellant rocket engines, dubbed "the heart" of the rocket.
-- Nuri was independently developed with South Korea's own rocket technologies -- from the design and manufacturing to testing and launching, a significant leap forward for a country that has so far relied on foreign resources for space launch vehicle development.
-- South Korea has launched a preliminary feasibility study for the successor to Nuri with the goal of sending a lunar landing module to the moon in 2031.
-- South Korea plans to conduct three more Nuri launches between 2025 and 2027 to improve the credibility of the space rocket and transfer technologies for Nuri development to private companies.
-- South Korea also plans to invest 2.01 trillion won by 2032 to develop a next-generation space rocket more advanced than Nuri. The advanced version will be a two-stage rocket using multistage combustion technology.