The JLENS system — which includes a pair of white, 243-foot-long balloons tethered to the ground — can stay in the air continuously for up to 30 days and is designed to spot missiles from 340 miles.
Its radar systems also can detect objects on the ground or water, including what security experts call “swarming boats,” the kind of small, agile watercraft that, when loaded with explosives, can threaten ships.
via Army surveillance balloons stationed in Maryland won’t include spy cameras – The Washington Post.
News links 