Nuri (Korean: 누리; Korean pronunciation: [nuriː], meaning "world" in native Korean), also known as KSLV-II (Korean Space Launch Vehicle-II),^[8] is a three-stage launch vehicle, the second one developed by South Korea and the successor to Naro-1 (KSLV-1).^[9] Nuri is developed by Korea Aerospace Research Institute (KARI).^{[10][11][3][12]} All three stages use indigenously developed launch vehicle engines, making Nuri the first indigenously developed South Korean orbital launch vehicle (the Naro-1 launch vehicle used a Russian-made first stage).

The South Korean government has set SpaceX as a "role model", striving to develop relatively cheap and reliable rockets competitive enough for the commercial launch market.^[13]

On 21 October 2021, Nuri made its initial orbital launch attempt at 08:00 UTC and it launched a 1,500 kg (3,300 lb) dummy satellite payload into what was planned to be a 700 km (430 mi) Sun-synchronous orbit (SSO). However, despite the payload reaching the targeted apogee (700 km), the third stage shut down about 46 seconds earlier than planned and the payload did not achieve orbital speed.^[12][14][15]

Nuri made its second flight on 21 June 2022, 07:00 UTC, with a payload of 1,500 kg (3,300 lb) including a 1,300 kg (2,900 lb) dummy satellite payload and a 180 kg (400 lb) performance verification satellite (PVSAT) including four cube satellites. The second launch was successful, putting all the satellites onto the 700 km (430 mi) Sun-synchronous orbit (SSO).^[16] As a result of this launch, South Korea became the seventh country in the world with the ability to put a satellite with a mass of at least one ton, into orbit.^[17][18]

After the two test launches, Nuri showed higher than expected performance, increasing its payload from 1,500 kg (3,300 Ib) to 1,900 kg (4,200 Ib).^[4]

Nuri is the first projectile developed with independent Korean domestic technology throughout all processes, including design, manufacturing, and testing. With its final successful launch, South Korea has become the seventh country in the world to have a medium-sized liquid-propellant rocket engine over 75 tons.^[19]

Nuri (KSLV-II) is a three-stage launch vehicle. The first stage booster uses four KRE-075 SL engines generating 266.4 tons of thrust with a specific impulse of 289.1 seconds. The second stage booster uses a single KRE-075 Vacuum engine, which has a wider nozzle for increased efficiency in vacuum with a specific impulse of 315.4 seconds. The third stage booster uses one KRE-007 engine with a specific impulse of 325.1 seconds. Both engine models use Jet A as fuel and liquid oxygen (LOX) as oxidizer.^[20]

When technology development for Nuri began by October 2010,^[20][22] the overall design goal was to develop a new expendable medium-lift launch vehicle that would be entirely developed with indigenous technology from Korea. As Nuri first reached orbit in June 2022, the total cost of the development program had been approximately US$1.5 billion.^[16]

Nuri will be used in launching several Earth observation satellites, such as KOMPSAT, medium-class satellites and LEO reconnaissance satellites. It is planned to support South Korea's Moon exploration mission to send orbiters and landers. Nuri will be South Korea's first launch vehicle to enter the commercial launch service market. The launch cost is estimated to be around US$30 million, which is cheaper than its Asian counterparts. This will allow for South Korea to provide cheap launch services for Southeast Asia countries.^[37]

South Korea plans to launch a high-weight rocket named KSLV-3 in 2030 instead of improving the KSLV-2. The decision is aimed at narrowing the technology gap with other countries.^[38]

Instead, it plans to develop a low-cost rocket that miniaturizes the KSLV-2 and is considering launching a military satellite to monitor North Korea.^[39]

• KSLV-I
• Naro Space Center
• KARI
• Comparison of orbital launcher families
• Comparison of orbital launch systems
• Comparison of orbital rocket engines