Lockheed Martin:

Known as ATHENA, for Advanced Test High Energy Asset, the ground-based prototype system burned through the engine manifold in a matter of seconds from more than a mile away. The truck was mounted on a test platform with its engine and drive train running to simulate an operationally-relevant test scenario.

My favorite bit of reading about the description of this thing is how carefully anyone avoids thinking about what it’ll do to a human when you point it at them. It’s being turned into a weapon for mounting on ground vehicles; it will be used against a human target, at some point in the future.