I have watched the documentary twice and find it very interesting. When offering an opinion as to whether or not this may have been an extraterrestrial craft I consider several things. First, I find that size inconsistent with experimental aircraft. Applying new or experimental technology to a craft this size goes against the logic of efficiency where budgets and defense department R&D is concerned. Next, I consider the history of similar sightings from highly reputable and credible witnesses. Rather than trying to suggest what it is I find it more reasonable to suggest what it isn't. Obviously, this object was not the Moon, Venus, a meteor or the Goodyear Blimp. That leaves two choices, either something top secret or something developed outside of our technological arena. Given the history of various sightings over decades I prefer to conclude the later. WTR