I say the “UO” is another pie plate on a string. You will notice a peg asymmetrically located on top of the object. This was done to give the object the tilt necessary to give it an illusion of independent flight as it hung by a fishing line from the upper power line.
Several investigators tried to determine the object’s distance using photo densitometric techniques and math analysis. What complicates the task are the camera lens, the film, how the film was developed and possible fog of the film due to poor darkroom light control. All these variables and efforts to pull it all together using scientific math analysis, had uncertain results. This is an impossible endeavor as the doctor found out. What you get is more art than science.
What is intriguing is the discussion about the change of shadows on the garage. If it were shown that the shadows determine that the object was shot at an interval longer than a couple of minutes, it would suggest that the photographer staged the two shots and took enough time to reposition the “UO” to get exactly what was wanted for the second shot. It would negate the idea that the “UO” stood around for any length of time for these photos.
Finally, what you have here are photos showing their characteristic Verichrome grain as they are enlarged. And the photographer did not have a camera with the lens quality to avoid the “fuzzy” photo misgivings I have about all of these “UOs.” Nor did the photographer do a very good job focusing his lens. It may have been the film speed of 64 that required him to open up his lens to, say, f-4 with the low light levels of overcast day. That would have degraded the sharpness of the photo. However, I can’t forgive him for the poor focus. Maybe he wanted to make sure the fishing line did not show up in the photograph.