A single black oval with moving frills

In Manassas, Virginia during the month of  September in ,2015. In the afternoon , My wife and I were seated in my car preparing to leave the parking lot of the Global Market on Sudley Road.
 When our attention was drawn to an black colored oval shaped object passing  slowly overhead from east to west.  Our initial thought was that it was a balloon. I kept our car in park and took out a pair of 8 - power binoculars, that  I keep for birdwatching and viewed the object.
 Through the binoculars,  it was definitely not a balloon. Approximately  two feet in diameter, completely black in color, with a sheen , like that of crude oil. It was moving smoothly , on a string straight trajectory unaffected by  a side wind. Emerging from and passing down equidistantly along either side of this object were frills , also of the same black color and texture. These frills emerged from and appeared to be reabsorbed into the object in a rythmic pattern. Aside from these frills, the object was  featureless. When it reached a bare tree within a yard , across Sudley Road, it stopped in mid- air. At that point I attempted to drive to the adjacent mall to get closer look at it , though it was gone, by the time we reached the mall.  No sound was noted. I have included a sketch.