North Korea conducts rocket engine test at Sohae space launch complex

North Korea appears to have conducted a rocket engine test at its Sohae space launch complex in Tongchang-ri, North Pyongan Province, last week, NK News reported Tuesday.

The U.S.-based North Korea-focused outlet said the test may be part of plans to revive leader Kim Jong-un's military reconnaissance satellite program.

Satellite imagery captured by U.S. commercial company Planet Labs shows signs of vegetation die-off on the hillside next to the vertical engine test stand between May 12 and Thursday, suggesting a rocket engine static test fire took place, NK News said.

In another sign of unusual activity, medium-resolution images from April 23 and 24 showed the rail-mounted protective shelter at the vertical stand pulled back, possibly to make room for pretest preparations or maintenance.

Because the test took place at a vertical engine test stand, it likely involved a liquid-fuel rocket engine. 

North Korea has not publicly reported the test.

Kim observed the test of a new solid-fuel engine for intercontinental ballistic missiles capable of striking the U.S. mainland on March 29. The display was interpreted as an attempt to distinguish North Korea, which possesses nuclear weapons capable of reaching U.S. soil, from Iran. North Korea publicized the test, which took place at the horizontal engine test stand.

Liquid-fuel missiles take longer to fuel and are less covert than solid-fuel ones, which has pushed North Korea to focus on solid-fuel engine development in recent years.

Other satellite images released by NK News show signs of a new structure being built inside the launch complex that may be a VIP viewing stand. The rectangular building, around 30 meters (98 feet) long and 12 meters wide, has been under construction since September. It features a taller middle section and shorter wings on either side.

NK News reported that Kim, during his March 2022 visit to the site, had ordered construction of "a grandstand in the safe zone opposite the launching ground."

The new building faces the coastal launchpad about 1.7 kilometers (1 mile) away. Workers appeared to install shelters over the front entrance and parking area in late April, and the road leading up to the building was paved on Saturday and Sunday.

The activity comes after Kim called for developing "further evolved reconnaissance satellites" at the Ninth Party Congress in February, where he laid out a new five-year plan. Engine tests have not always preceded satellite launches, NK News noted, but one came weeks before the last attempt in 2024.

North Korea has made four attempts to launch military reconnaissance satellites since 2023. The first two failed before the regime claimed in November 2023 that its third attempt had successfully placed the Malligyong-1 satellite into orbit. The fourth attempt in May 2024 failed when the first-stage booster exploded in midair. There have been no further satellite launches since.

This article was originally written in Korean and translated by a bilingual reporter with the help of generative AI tools. It was then edited by a native English-speaking editor. All AI-assisted translations are reviewed and refined by our newsroom.

BY CHO MUN-GYU [cho.yongjun1@joongang.co.kr]