Live footage showed the 47-meter (154 foot) rocket soaring into the air with bright yellow flames shooting out of its engines following blastoff at Naro Space Center, the countryâs lone spaceport, on a small island off its southern coast.
After the launch, the Korea Aerospace Research Institute, the countryâs space agency, reported that Nuriâs first and second stages separated properly and that the third stage carried the payload â a 1.5-ton block of stainless steel and aluminum â 700 kilometers (435 miles) above Earth. But Moon, who observed the launch at the Naro spaceport, said in a televised speech that the payload didnât stabilize in orbit after being separated from the third stage.
Officials from KARI and the countryâs Science Ministry didnât immediately provide more details on what went wrong.
The launch, which took place at 5 p.m. (0800 GMT), had been delayed by an hour because engineers needed more time to examine the rocketâs valves. There had also been concerns that strong winds and other conditions would pose challenges for a successful launch.
âAlthough (the launch) failed to achieve its objectives perfectly, it was an excellent accomplishment for a first launch,â Moon said.
âThe midair engine ignitions and the separations of the rockets, fairings (covering the payload) and the dummy satellite worked smoothly. All this was done based on technology that is completely ours,â he added.
After relying on other countries to launch its satellites since the early 1990s, South Korea is now trying to become the 10th nation to send a satellite into space with its own technology.
Officials say such an ability would be crucial for the countryâs space ambitions, which include plans for sending more advanced communications satellites and acquiring its own military intelligence satellites. The country is also hoping to send a probe to the moon by 2030.
Nuri is the countryâs first space launch vehicle built entirely with domestic technology. The three-stage rocket is powered by five 75-ton class rocket engines placed in its first and second stages.
Scientists and engineers at KARI plan to test Nuri several more times, including conducting another launch with a dummy device in May 2022, before trying with a real satellite.
South Korea had previously launched a space launch vehicle from the Naro spaceport in 2013, which was a two-stage rocket built mainly with Russian technology. That launch came after years of delays and consecutive failures. The rocket, named Naro, reached the desired altitude during its first test in 2009 but failed to eject a satellite into orbit, and then exploded shortly after takeoff during its second test in 2010.
It wasnât clear how North Korea, which had been accused of using its space launch attempts in past years as a disguise for developing long-range missile technology, would react to Thursdayâs launch.
While pushing to expand its nuclear and missile program, the North had shown sensitivity about South Koreaâs increasing defense spending and efforts to build more powerful conventionally armed missiles.
In a speech to Pyongyangâs rubber-stamp parliament last month, North Korean leader Kim Jong Un accused the U.S. and South Korea of âdestroying the stability and balanceâ in the region with their allied military activities and a U.S.-led âexcessive arms buildupâ in the South.
While Nuri is powered by liquid propellants that need to be fueled shortly before launch, the South Koreans plan to develop a solid-fuel space launch rocket by 2024, which could be cheaper to build and prepared for launch more quickly. Such rockets would also be ideal for more sensitive space launches, including those involving military intelligence satellites.
South Koreaâs space ambitions received a boost in recent years as the Trump and Biden administrations took steps to ease decades-long U.S. restrictions that capped Seoulâs missile development before eventually allowing its ally to build conventional weapons with unlimited range and warhead weight. In easing the so-called missile guidelines, the U.S. also removed a limit on how powerful solid-fuel rockets South Korea can build for space launch purposes.
South Korea currently has no military surveillance satellites of its own, which leaves it relying on U.S. spy satellites to monitor North Korea. Officials have expressed hopes of launching domestically developed, low-orbit military surveillance satellites using the countryâs own solid-fuel rockets in the next several years.