'It's very, very large': Experts dissect the new images of North Korea's sophisticated missile

North Korea released a slew of photos Thursday, showing off the record-breaking intercontinental ballistic missile the isolated nation launched a day earlier.

Missile experts were impressed. “This is biggest development in a year of big developments,” said Jeffrey Lewis, an analyst at the Middlebury Institute of International Studies.

Here’s why:

'It’s very, very large' 

The missile, called the Hwasong-15, is the biggest yet, which explains it’s long range,  Lewis said. The first stage appears to have two large engines, capable of about 80 to 100 tons of thrust, Lewis said. The Hwasong-15 tested Wednesday reached an altitude of 2,780 miles, the highest yet. It would have had a range of 8,100 miles had it flown in a flat trajectory, according to calculations by David Wright, an expert at the Union of Concerned Scientists. That would make it capable of reaching Washington, D.C. 

Blunter nose cone 

The upper stage is also large, allowing the North Koreans to choose between outfitting it with a larger thermonuclear bomb, decoys that could help avoid defending against U.S. interceptors or multiple warheads, Lewis said. It has a blunter nose cone, which could help slow the warhead and make for a smoother transition into the earth’s atmosphere.

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Re-entry has been a challenge for North Korean missile designers. “The nose cone appears to have gone back to an older design,” said David Albright, president of the Institute for Science and International Security. But that design could also slow the missile and make it more vulnerable to being intercepted, he said.

Improved steering 

The thrusters on the first stage appear to be able to swivel, allowing the missile to be steered more efficiently. More primitive rocket designs use fins for steering, which can cause drag and reduce speed and range. “That’s a fancy new trick we haven’t seen before,” Lewis said.

North Korean-made truck?

The launcher was mounted on a larger truck than previous missiles. Perhaps even more alarming is the truck may have been built by a North Korean factory, since the photos released Thursday were taken in an automotive factory. Most previous launch vehicles were Chinese-made. “They can build as many as they need,” Lewis said, without having to rely on the Chinese. The mobile launchers are important because they can make it more difficult for the United States to detect a launch before it happens. By contrast, fixed sites can be continuously watched. “They wanted to demonstrate they could attack without warning,” Albright said.