For years, the US military has been developing an Advanced Hypersonic Weapon, a type of missile system designed to fly at hypersonic speeds (over 3,600 miles-per-hour, or five times the speed of sound) and reach any target in the world in an hour or less. But a recent test launch of the weapon didn't go so well: as the US Defense Department acknowledged in a statement, the Advanced Hypersonic Weapon's launch from a site in Alaska early Monday morning had to be "terminated near the launch pad shortly after lift-off to ensure public safety." In plain English: "The weapon exploded during takeoff and fell back down in the range complex," as Defense Department spokesperson Maureen Schumann told NBC News.
The news is obviously not spectacular for the military, which has described the weapon as having the "potential to change warfare forever." But it's only the second test flight of these particular capabilities, following a successful flight in November 2011. And with the US Army staying within the limits of its budget and China also testing its own hypersonic glider, development on the American weapon is almost certain to proceed. The Defense Department hasn't yet released footage or photos of the latest aborted test flight, but a local photographer caught a frighteningly bright fireball from over 12 miles away. You can see his photos here and here.