As it happens Alex, I saw a UFO earlier this week. It lasted about 10 seconds before morphing into an Interesting Optical Illusion (IOI).
I was in the backyard taking advantage of the clear skies when I saw a 'bird' flying low over the garage roof. A fairly large, light coloured bird ... but no that's no bird ... nor a bat ... ahh! a balloon or large piece of plastic ... but it's moving fast to the north and there is but a zephyr of breeze from the west .... what the ??? Luckily I had the binos read to hand and soon found it was a small flock of water birds flying in 'V' formation. My eye connected the individual shapes into one - they were close together - and then filled in the area between the arm of the V. Because they were so low I had a fairly side-on view and so as the birds' relative position changed it produced a 'flapping' illusion. I've since noticed quite a few flocks going over, all going north, but the rest have been pretty much overhead and so easier to recognise. Besides, I'm a bit wiser now.
BTW. I always find it strange that people think they now how far away a light is - especially if it isn't moving. I've been surprised on many occasions at how close or distant a light has turned out to be; and mostly they were further away than I thought. As astronomers I think we need to be aware that light can travel vast distances and not get tired
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