Saw aircraft hovering in the sky with white lights on corners, close to ground, slate colored, silent.

Aircraft larger than a plane suspended in the air. It had lights on it like a plane, but was just hovering. It was triangular in shape and slate colored.
We were headed East bound on State Street when we saw the aircraft hovering on the south side of the street. No noise, no movement. We drove up to the nearby dog park to turn around to get video/pictures. There are trees in between the dog park and conservation area so as we were headed down the gravel drive to turn around the craft became out of sight. We turned around, came back out, turned West onto State street and the aircraft was gone without a sound or any sign that it took off.