Black object effortlessly floated without the use of wings or engine.

Me and my friends were sitting outside playing cornhole. A black object flew at a very stable speed and kept the same altitude. It almost looked like a giant black garbage bag floating in the wind but a few hundred feet above the ground. It came in the direction over the Delaware river and moved northeast. It was the most effortless thing I have ever seen move in the air. There sometimes are paramotors in the air and we all are very aware of what a paramotor looks like when it flies. The strangest thing was that we did not see any signs of an engine, wings, chute, or anything. It just seemed like it was drawing a very straight line without having control.