On Tuesday, August 18th of this year, I saw a large object while driving northwards on the interstate to my 10 o'clock flying over a mountain to the north end of Tremonton, Utah. The object was shaped very similar to a paraglider, although the object had nothing dangling beneath, nor did it have the actual cells of a paraglider. It was a very very dark grey in color. The two most frightening, or interesting features of this object were its size, it was at least 500 yards from tip tip, and 200 from stern to aft, the second, most striking feature was that it would fade into invisibility, to full visibility, and did so repeatedly, all while in its constant doing its constant figure 8 parallel to the surface of the mountain. It did so until the object remained invisible, and didn't come back. The ordeal lasted several minutes.