Alarms sound in Japan as North Korea fires missile

The Japanese emergency alert systems on Thursday warned people on its second-largest island, Hokkaido, to take cover, saying a North Korean missile could land on or near the island. Japan retracted the alert after determining the missile would not hit the island. North Korea’s first intercontinental ballistic missile launch since March landed outside Japan’s territory. South Korea’s military thinks the missile may have used solid fuel, a first for North Korean technology, an anonymous defense official told the Associated Press.

Why is solid fuel advantageous? A solid-propellant weapon is constantly loaded, allowing it to be moved more easily and fired faster than one that uses liquid propellant. An ICBM that uses liquid propellant has to be fueled before launch. North Korean leader Kim Jong Un has vowed to create a solid-fuel ICBM—along with a multiwarhead missile, a nuclear-powered submarine, a hypersonic missile, and a spy satellite. 

Dig deeper: Read Joyce Wu’s report in World Tour on North Korea’s neighbors shoring up their defenses.