South Korea’s Space Program: Catching up with the Pack

South Korea, in some ways, was destined to develop rocket technologies. When a fragile peace was established with North Korea in 1953, ballistic missile technology seemed to be the only true guarantor of that peace. South Korea later realized that missiles could carry not only warheads but also payloads in the form of communication and observation satellites. 

Today, we will examine how, in less than 35 years, Seoul managed to develop its aerospace sector, coming close to catching up with the world’s leading spacefaring nations.

The establishment of KARI and the domestic development of launch vehicles. 

South Korea was significantly late in launching its own space program. The Korea Aerospace Research Institute (KARI), the country’s leading aerospace enterprise and research laboratory, was only established in 1989, at a time when most countries in the region were already using domestically produced launch vehicles and satellites. This delay was largely due to the difficult economic situation in the country following the armistice in 1953.  

As a result, the newly created KARI had to work at double speed to catch up with its competitors. The main reasons for its establishment were similar to those of analogous institutions worldwide: Seoul sought to develop space technologies to enhance its national security, improve the country’s economic situation, and integrate space technologies into a wide range of civil and military activities.  

In the early 1990s, KARI developed the first versions of the Korean Sounding Rocket (KSR) series. Two different modifications were designed almost simultaneously: the single-stage, solid-fueled KSR-1 and the two-stage, solid-fueled KSR-2. These were suborbital rockets designed specifically to deliver small satellites to low altitudes. At the time, however, even this mission proved unattainable.  

The first demonstration of the KSR-1 took place in 1993. The unguided rocket managed to reach an altitude of 39 km, which was far from sufficient for deploying satellite payloads. The second launch of the KSR-1 (mission KSR-420S-2) slightly improved the altitude to 49 km. It became clear that Seoul would need more powerful rockets to begin truly independent space activities.  

A modified version of the first-generation rocket, the two-stage KSR-2, was capable of lifting a 150 kg payload to an altitude of 137 km. Only two demonstrations of the KSR-2 were conducted, in 1997 and 1998. The project was then discontinued, and KARI’s main efforts shifted to the new generation KSR-3 rocket, which debuted in the early 2000s.

The KSR-3 represented a new way of thinking about rocket design. First, KARI engineers decided to move away from the concept of a solid-fueled propulsion system and instead used a liquid-fueled engine that ran on a mixture of liquid oxygen and kerosene (LOX/rac). During testing in 2002, the rocket was able to climb to an altitude of 42.7 km and fly 84 km. It is worth noting that KSR-3’s maximum altitude, which was lower than that of the KSR-2, was due to its greater weight, which was three times higher (6.1 vs. 2 tons). The specific thrust achieved at the launch of the KSR-3 was 13 tons.

Of course, the KSR rocket series was not capable of carrying out serious space missions, and the main achievement of the program was sensing the lower atmosphere over the Korean Peninsula and measuring ozone concentrations using an ultraviolet radiometer. At the same time, there were concrete security benefits associated with South Korea’s acquisition of this type of ballistic missile given ongoing tensions between Seoul and Pyongyang.

However, the KSR program’s most significant achievement will be the experience KARI gained from developing its own rocket technologies. It will form the basis for the design of the future KSLV-1 and KSLV-2 (Korea Space Launch Vehicle), which will finally conquer orbit. 

Grown-Up Games: The Emergence of the KSLV

From the beginning of the KSLV’s development (known in Korea as Naro-1, after the newly built spaceport from which its launches took place), the project faced a host of challenges. The most important issue was the need to build a reliable and powerful main engine for the rocket’s first stage. In October 2004, the South Korean government turned to Russian experts for assistance in designing this crucial system.  

The decision was made to base it on Russia’s single-chamber, liquid-fueled RD-151 engine, which ran on a mix of kerosene and liquid oxygen. The RD-151 was a less powerful and lighter version of the RD-191, which Roscosmos planned to use for launching its new family of “Angara” launch vehicles. A single two-ton RD-151 engine, capable of generating 75 tons (1,670 kN) of thrust at launch, was designated for the Naro-1’s first stage.

It seems surprising in hindsight, but the choice to use Russian technology was partly due to the fact that, in the early 2000s, the United States actively obstructed Seoul’s efforts to develop its own launch vehicles. This was driven by U.S. concerns that South Korea’s development of rocket weaponry could escalate tensions with North Korea.  

In 2008, Russia delivered the completed first stage of the future KSLV-1, which was designed by NPO Energomash. At that time, KARI was still working on the rocket’s second stage, which was to be an entirely Korean design that ultimately used a solid-fueled engine capable of generating 86.2 kN of thrust.  

It is worth noting that throughout the development phase, South Korea faced significant challenges in funding the project. Starting in 2002, approximately $450 million was spent, a substantial financial burden for the country.  

Despite the considerable investment, the KSLV-1 only managed three launches, two of which failed. The first launch took place on August 25, 2009, resulting in the loss of the payload during the separation of the first and second stages. A year later, in June 2010, the second KSLV-1 launched from the Naro Space Center, but exploded mid-air at the 137th second of the mission. Two expert panels investigated the Naro-1 failure for over a year but could not reach a definitive conclusion on the cause of the rocket’s loss.  

For the next 2.5 years, KARI paused its efforts, making another attempt to launch the KSLV-1 only on January 30, 2013, the KSLV-1’s only successful launch.

The rocket successfully placed the STSat-2C research satellite into orbit. Developed by KARI, this satellite was designed as a demonstration of spacecraft separation and deployment technology for orbital laser tracking and communication. The Korean research institute saw STSat-2C as the first building block in a future manned spacecraft program.  

However, such successes could not delay the inevitable: by 2013, the rocket that KARI had been developing for the past seven years was declared outdated and in need of replacement with a new, more powerful version. Work had already begun by 2010 on the design of the Naro-1’s successor, the three-stage KSLV-2 (or Nuri), whose stages were all to be manufactured domestically in Korea.  

The KSLV-2 was designed to have the capability to launch large satellites weighing up to 1.5 tons into a sun-synchronous orbit at an altitude of 600–800 km (with plans to later increase the payload capacity to 1.9 tons). KARI openly admitted that the rocket’s design drew inspiration from SpaceX’s Falcon 9 and aimed to come as close as possible to the economic and technological benchmarks set by Elon Musk’s company.  

The cost of the new rocket project rose significantly, with the South Korean government investing nearly $1.7 billion. Among other advancements, a new version of a vacuum engine for the rocket’s second stage, the KRE-075, was developed from scratch. This engine was capable of generating 75 tons of thrust.

Nuri’s first launch took place on October 21, 2021, and ended in failure. Issues arose with the rocket’s third stage, which shut down nearly a minute earlier than planned. As a result, while the payload reached the intended altitude of 700 km, it failed to achieve the necessary orbital velocity and re-entered Earth’s atmosphere.  

KSLV-2 did achieve success on its second attempt. On June 21, 2022, the rocket delivered a payload of 1.5 tons into orbit. This payload included four scientific CubeSats weighing 5 kg each, the PVSAT satellite weighing 180 kg, and a 1.3-ton dummy payload designed to test separation and deployment technologies in orbit.  

The most recent KSLV-2 launch occurred on May 25, 2023, when the rocket placed 240 kg of payload into low Earth and sun-synchronous orbits. Among the payloads were four satellites for ionospheric and magnetospheric research (SNIPE), the NEXTSat-2 demonstration satellite, the JLC-101-v1-2 monitoring satellite, equipped with a highly sensitive optical camera, the Lumir-T1 CubeSat for measuring radiation levels in the upper atmosphere, and the KSAT3U weather satellite.  

Currently, KARI is developing a new variant, the KSLV-3 TBD, which will be capable of delivering large payloads to geostationary equatorial and geosynchronous Earth orbits. The rocket is planned to feature four boosters in the first stage, each equipped with a KRE-090 vacuum engine. The rocket’s second stage will also be powered by a KRE-090V engine (a less powerful variant of the KRE-090). For the third stage, KARI has designed an entirely new liquid engine, the KRE-010V, which operates on an oxygen and kerosene mixture.

It is worth noting that, throughout the history of KSLV rocket family launches, South Korea has never delivered commercial payloads from foreign countries into orbit — all of its satellites have been internal developments from various Korean research institutes and laboratories. Seoul largely focuses its efforts, not on earning money from commercial clients, but on improving its own space technologies. Despite the significant boost this policy gives to the national aerospace sector, it also raises questions from critics: the situation in which South Korea invests money into the space sector, year after year, without actually earning any revenue from its launches is quite unusual.

The origins of the satellite program

While KARI was focused on the development of launch vehicles, another Korean institution, the Korean Institute of Technology (KIT), began producing its own satellite devices. In 1989, KIT merged with the Korea Advanced Institute of Science and Technology (KAIST), marking the active phase of South Korea’s satellite program.

The first project pursued by the newly-merged KIT/KAIST (hereafter referred to simply as KIT) was the development of a small satellite for low Earth orbit (LEO), the KITSAT-1, which was launched from the Guiana Space Centre in French Guiana on August 10, 1992, aboard the European Ariane 4 rocket.

The satellite’s orbit, which was 1316×1328 km, was the highest of all of the LEO satellites launched by South Korea over the next 32 years. The spacecraft was intended to demonstrate Seoul’s capabilities in developing its own satellite devices and, thanks to its launch, South Korea became the 22nd country in the world to be capable of doing so.

KITSAT-1, however, was not purely a Korean project. The development of some of its instruments involved specialists from the UK’s Surrey Institute and its satellite division, Surrey Satellite Technology Ltd (SSTL), which specialized in creating small satellites. In collaboration with their South Korean counterparts, SSTL engineers were able to develop and construct the satellite bus and four main scientific instruments for KITSAT-1 in just a few years.

First, the spacecraft was equipped with a PACSAT (PCS) satellite communication system, with a data transfer rate (both uplink and downlink) of 9.6 kbps. KITSAT-1 also conducted a digital signal processing experiment (DSPE). Another purely scientific experiment (CRE) focused on the search and study of cosmic ray composition.

KITSAT-1 was a very small satellite (weighing only 48.6 kg), but it was equipped with two digital optical cameras for Earth observation, which together made up its fourth and final instrument, the Earth Imaging System (EIS). Naturally, the size did not allow for the installation of highly sensitive optics, so its first, a television camera, could capture images with a resolution of 400 m per pixel, while the second, a wide-angle camera, provided panoramic images of the Earth’s surface with a resolution of 4 km per pixel. For comparison, modern optical satellite sensors have reduced this threshold to half a meter per pixel or even less.

KITSAT-1 was designed to operate in orbit for at least five years, but its mission lasted seven years longer than planned: support for the probe was finally terminated only in 2004. The success of the first satellite mission allowed KARI to plan new projects, and just a year after the launch of KITSAT-1, on September 26, 1993, its next modification, KITSAT-2, was launched.

Structurally, the second KITSAT resembled its predecessor, but it contained more scientific equipment. This included the KAIST computer (or KASCOM), which was capable of processing real-time data from KITSAT-2’s measurement devices, storing it, and sending it to Earth using its own digital storage and direct communication system (DSFCE). The satellite was also equipped with a new low-energy electron detector (LEED) and an infrared observation sensor (IREX).

In late May 1999, KIT launched the next KITSAT-3, whose primary task was Earth observation. For the launch of this spacecraft, the cheaper Indian PSLV rocket was chosen, which by then had only carried out its second operational launch.

However, the key difference for KITSAT-3 was not its reoriented mission profile or new scientific equipment, but the fact that it became the first satellite entirely constructed by South Korean specialists from the combined KIT and KAIST, with no help from foreign contractors.

Later, SaTReC (Satellite Technology Research Center), South Korea’s leading satellite manufacturer, was established at KAIST. To this day, SaTReC remains the country’s main manufacturer of satellite buses and scientific instruments. The company has been involved in the development of over 20 satellite devices for different countries, including Spain’s Deimos 2, Turkey’s Göktürk 2 monitoring satellite, and Malaysia’s RazakSAT, among others.

Of course, SaTReC has also been involved in the production of its own satellites. Between 1999 and 2020, SaTReC specialists developed the KOMPSAT series of Earth observation satellites, which includes several modifications. Some of them, including the KOMPSAT-5 and KOMPSAT-3A, were launched into orbit by the Ukrainian Dnepr rocket.

However, South Korea continues to order some types of satellites from Western contractors. For instance, the military ANASIS II satellite, launched on July 20, 2020, was developed by the European aerospace company Airbus Defence and Space at Seoul’s request.

In general, unlike in the rocket sector, the satellite sector shows active involvement in various international projects, making South Korea one of the leading suppliers of satellite hardware and sensors in the world. Today, SaTReC serves as the foundation for a range of related companies and business incubators, where Seoul is nurturing new talent for the development of this space industry sector.

Cooperation with the United States 

The success of South Korea’s space program would not have been as rapid without the involvement of its key strategic ally, the United States. Although at the end of the last century, the U.S. had actively restrained the development of Seoul’s rocket and space sector, this policy was later abandoned.

The May 2021 Agreement on Civil Global Navigation Satellite Systems Cooperation between the United States and South Korea facilitated the exchange of satellite technologies with NASA and allowed Seoul to develop and launch the Korean Positioning System (KPS), an analog to the U.S. GPS.

By 2035, South Korea plans to launch eight satellites into orbit as part of this constellation, significantly strengthening its space navigation and awareness sector, which will contribute to national security. As of 2021, the estimated budget for the KPS geolocation program was around $3.3 billion.

The new navigation system is expected to consist of three satellites placed on geostationary orbit (GEO) and five on inclined geosynchronous orbit (IGSO). Together, they will provide 24/7 coverage of the entire Korean Peninsula and offer precise real-time navigation for autonomous vehicles, civilian and military aviation, maritime transport, and other future innovative products and services that require highly accurate location information.

Active support from the United States on the project will primarily focus on developing satellite equipment for signal reception and transmission. This collaboration will significantly reduce positioning errors, which for most modern GNSS (Global Navigation Satellite Systems) systems is approximately 20 meters. Under the most optimistic scenarios, it may be possible to decrease this to just 2.5 centimeters. The joint American-Korean project is expected to create around 60,000 jobs in South Korea.

Close cooperation with NASA has also led to the development of the first South Korean lunar spacecraft (currently only lunar orbiters). The Korea Pathfinder Lunar Orbiter (KPLO), or Danuri, has participated in the preparatory phase of NASA’s Artemis. The spacecraft was launched in August 2022 aboard a Falcon 9 rocket and embarked on a four-month-long journey to reach the Moon. This extended journey is due to a specialized ballistic transfer trajectory designed to minimize fuel consumption. 

Danuri successfully entered lunar orbit on December 16, 2022. Over the more than 800 days it orbited the Moon, the spacecraft conducted numerous experiments to establish stable satellite communication and transmitted terabytes of high-resolution data back to Earth.

Currently, the United States remains South Korea’s primary partner in both the civilian and military space sectors. Given the constant–and escalating–threat from North Korea, Seoul is continuously strengthening its integration into the American missile warning system and is working to develop a joint strategy for conducting space operations. As of today, both countries plan to establish a joint military advisory body focused on building a sustainable space security structure.

KASA as a platform for civil space development

Recently, South Korea’s space program was finally separated into a purely civilian division, which was named the Korean Aerospace Administration (KASA), similar to the structures that oversee the development of the private civilian aerospace sector in the United States. 

The newly formed KASA will focus on strengthening horizontal commercial and industrial connections within the country to enhance its competitiveness in the global space arena. However, KASA’s plans are not particularly ambitious at this stage, as they are focused on launching a robotic lunar landing platform only in the early 2030s, with a similar Martian probe scheduled for the mid-2040s.

These preliminary plans are significantly behind other major space players in the region. India (Chandrayaan 3), China (Chang’e 6), and Japan (SLIM) have all already sent landing platforms to the Moon. However, Japan’s SLIM lander faced a partial failure when the spacecraft tilted during its landing. As a result, Seoul’s plans to catch up with these countries by 2032 seem rather ambitious, despite the fact that South Korea has already sent its miniature lunar probe Danuri to the moon, with its data being used by NASA to prepare for future lunar missions under the Artemis program.

Nevertheless, KASA doesn’t seem to be aiming for major triumphs, instead focusing this decade solely on the modest work of strengthening its own aerospace sector. Currently, KASA is working hard to significantly increase venture investments. Today, such investments amount to about $720 million, but, by 2045, when KASA plans to travel to Mars, the administration hopes to invest the equivalent of $72 billion into the national space program.

If everything goes according to plan, within a decade KASA could indeed become one of the leading space agencies in the world. For sustainable development, South Korea only needs peaceful skies above.