Tethered Aerostat B-44 - Eagle Pass

It's shadow can be seen way up to the NNE.

The Tethered Aerostat Radar System is a balloon-borne radar system. The primary aerostat mission is to provide low level radar surveillance data in support of federal agencies involved in the nation's drug interdiction program. Secondary mission is to provide North American Aerospace Defense Command with low level surveillance coverage for air sovereignty in the Florida Straights.