South Korea’s First Homemade Rocket Launch Declared a Partial Success

SEOUL — South Korea launched its first homemade rocket on Thursday, a mission that was only partly successful but that officials called an important step toward ​placing domestically made satellites in orbit to better monitor growing threats from North Korea.

The three-stage Nuri rocket, built by the government’s Korea Aerospace Research Institute with the help of hundreds of local companies, lifted off from the Naro Space Center in Goheung, on the southwestern tip of South Korea. The rocket carried a 1.5-ton dummy payload to test its ability to thrust an artificial satellite into orbit 373 to 497 miles above the Earth.

A little more than an hour after the takeoff, President Moon Jae-in said the launching “did not reach its goal completely” but showed “excellent results for a first try.” He said Nuri pushed its payload to space 434 miles above the Earth but the mission was “incomplete.” Mr. Moon provided no further details, but experts said that the dummy satellite probably did not operate at the altitude or speed its engineers had intended.

“We were just one step short of reaching our goal,” Mr. Moon said during a news conference, urging engineers to make the next launch, scheduled for May, “a complete success.”

The launch on Thursday was broadcast live on all major TV stations and on internet streaming platforms like YouTube. Mr. Moon’s government had billed the launch as a giant step forward in South Korea’s effort to become a new leader in space technology.

South Korea has nurtured a decades-long ambition to join the elite club of nations building rockets capable of placing communications, surveillance and other satellites in orbit. After multiple delays and failures, South Korea’s Naro rocket succeeded in putting a satellite in orbit for research and development purposes in 2013. But unlike Nuri, the rocket launched on Thursday using domestic technology, Naro was built jointly with Russia.

South Korea has spent nearly $1.7 billion to build the 200-ton Nuri, also known as the Korea Space Launch Vehicle-II. It planned to conduct several more trial launches of the Nuri system, including one scheduled for May.

With Nuri, South Korea has hoped to secure a foothold in space technology, the latest high-tech market where the country has decided to become a player. Most rocket launches around the world have been carried out by the United States, Russia, France, China, Japan and India.

South Korea plans to send a moon orbiter next fall aboard a Falcon 9 rocket from SpaceX, the company founded by Elon Musk. Mr. Moon has said that his country expects to be able to land an uncrewed spacecraft on the moon using South Korean rockets by 2030.

With its own rocket capabilities, South Korea says it hopes to build satellite-based navigation and next-generation communications networks. It also wants to carve out a portion of the world’s satellite-launching market, an increasingly crowded field as major industrialized countries jostle to build their own domestic programs.

The Nuri launch also reflected South Korea’s desire to be less dependent on United States forces to monitor North Korea, as well as its goal of regaining wartime operational control of its 550,000-member military. Under a bilateral agreement with Washington, South Korean troops fall under the command of an American general should war break out on the Korean Peninsula.

South Korea has no military spy satellites of its own, relying instead on United States satellites to watch the North. Placing its own “eyes and ears” in space became more urgent as North Korea’s nuclear and missile capabilities expanded​ over the years and after President Donald J. Trump threatened to withdraw American troops​ in South Korea.

South Korea placed its first military communications satellite into orbit last July, carried by a SpaceX Falcon 9 rocket​.

North Korea, which has its own rocket program, has criticized the South’s space program​ for its potential military applications​. Space rockets and intercontinental ballistic missiles use similar technologies. North Korea launched satellite space vehicles before it successfully tested three I.C.B.M.s in 2017. The United Nations Security Council banned the North from launching space rockets that were being used as tests for the country’s long-range ballistic missile program.

South Korea’s space ambitions have been hamstrung for years by agreements with the United States. American officials feared that a robust South Korean rocket program would lead the country to build missiles, accelerating a regional arms race. But last year, Washington and Seoul agreed to remove some of the restrictions, allowing South Korea to build solid-fuel rockets for space-launch vehicles.

Solid-fuel rockets are more cost-effective than liquid-fuel rockets like Nuri. They are also ideal for long-range ballistic missiles because they are easier to transport and prepare for launch. North Korea has accused the South of hypocrisy for expanding its own weapons capabilities while criticizing the North’s.