The second coming
Jokes aside, I have no answer! I’ve looked at the video too many times. It’s got me stumped, aside from an extraterrestrial explanation I can’t think of anything.
It’s shape, velocity, trajectory and last second change of direction. I know of nothing that could do that in that environment in 1984. Let alone now.
Sounds out there but maybe the whole thing was being observed, like we observe animals using basic tools. A probe?