By Jun Ji-hye
North Korea’s latest launch of the mid-range missile shows Pyongyang might have made progress in re-entry technology necessary to bring a nuclear-armed ballistic missile back into the Earth’s atmosphere, analysts said Thursday.
Military officials here are paying keen attention to the report that the North’s Musudan intermediate-range ballistic missile (IRBM), launched Wednesday morning, reached an altitude of more than 1,000 kilometers above sea level and then landed in the East Sea.
This means that the Musudan flew into space and returned to Earth, given that the Karman line at an altitude of 100 kilometers is usually used as the border between the atmosphere and outer space.
The IRBMs, believed to have a range of 3,000 to 4,000 kilometers, could strike any target in Japan and also reach Guam, home to U.S. naval and air bases.
A military official here said on the condition of anonymity that this was the first time one of the North’s missiles has reached an altitude of more than 1,000 kilometers and returned to Earth.
But the official added that verification is needed as to whether or not its warhead was damaged while re-entering the atmosphere.
If the North has actually acquired the capability of re-entry, it would mean that the regime is in the final stages of developing middle- and long-range ballistic missiles, according to experts.
When announcing the successful launch of the “Hwasong-10,” the name of the Musudan in the North, Thursday, the North’s Korean Central News Agency (KCNA) claimed that the missile reached a maximum altitude of 1,413.6 kilometers and fell precisely onto a designated target 400 kilometers away in the sea.
Japan’s Defense Minister Gen Nakatani told reporters in Tokyo that the North’s missile soared to an altitude of more than 1,000 kilometers.
Securing missile re-entry technology is cited as the toughest challenge in developing operational middle- and long-range ballistic missiles. As missiles re-enter the Earth’s atmosphere at Mach 20, the missile’s warhead needs to be capable of withstanding temperatures of around 6,000 to 7,000 degrees Celsius.
The KCNA said that Wednesday’s launch verified the heat-resistant capability of the missile warhead as well as its flight stability.
Lee Choon-geun, an analyst from the Science and Technology Policy Institute, told reporters that the reentry speed of the latest launch is believed to have been faster than usual as the North used an acute high-arc trajectory this time.
“If there was no problem when the missile re-entered the atmosphere even when an acute high-arc trajectory was used, it can be seen that the North has made progress in missile re-entry technology of not only the IRBM, but also of an intercontinental ballistic missile (ICBM),” he said.
The North’s KN-08 ICBM has yet to be tested and is believed to have a theoretical range of more than 10,000 kilometers, far enough to reach the contiguous United States.
In March, North Korean leader Kim Jong-un claimed, through state-run media, that the regime has “proudly acquired re-entry technology, thus making great progress in the ballistic rocket technology that helps strengthen independence.”
Kim made the remark after a ground test for estimating the heat stability of a rocket warhead and the erosion of heat-resistant coating material, the KCNA said, adding that the test guaranteed “the reliability of inter-continental ballistic rocket warhead reentry.”
However, the South Korean military said it is too early to say that the North acquired re-entry technology.
“Additional analysis and verification are necessary to say that,” said the Joint Chiefs of Staff (JCS) spokesman Col. Jeon Ha-kyu.
But he added that there seems to have been some progress in the North’s technology involving missile engines, given that the missile fired Wednesday flew around 400 kilometers, while previous ones exploded right after launch.