NPR reports: At 2:17 p.m. on May 6, 1962, a nuclear-tipped missile shot out of the waters of the Pacific Ocean and quickly disappeared into the sky. Roughly 12 minutes later and over 1,000 miles to the southwest, it detonated in a blinding flash — creating a mushroom cloud over an empty stretch of water.

The test was of a submarine-launched Polaris A-2 missile. It was code-named “Frigate Bird,” and it was America’s first, and only, end-to-end test of a nuclear missile.

Thus far, North Korea has tested its nuclear weapons and ballistic missiles separately. The nukes have detonated in deep underground chambers, while the missiles have flown on “fly-ball” trajectories that take them high into space while limiting their range.

But in the wake of the North’s most recent underground test, and with rumors of another ballistic missile test coming soon, some experts now fear that a Frigate Bird-type test may be coming.

“That would be the ultimate way for North Korea to prove its capabilities,” says James Acton, a physicist and co-director of the Nuclear Policy Program at the Carnegie Endowment for International Peace. “I very, very much hope we don’t go there.” [Continue reading…]