Some people report erratic motion of the objects which you wouldn't expect from a normal plane or helicopter.
If the lights on the things are blinking, I have a possible explanation for the erratic motion.
I've found that if I'm in a dark place with a green LED that is blinking and there is not enough light to see anything but the LED then the LED appears to jump around erratically.
I'll see it come on and go off and I'm sure that I am continuing to stare at the now off LED but when it comes on it is somewhere else. If I'm about 40 cm from the LED it can appear to have jumped up to maybe 15-20 cm.
It can be quite disconcerting if there is a series of apparent jumps in the same direction, because each time I have to move my eyes/head in the same direction to recenter the LED, and after 4 or 5 jumps it feels like I should be turned significantly but I can tell that I'm actually still looking mostly straight ahead.
If I arrange for their to be some faint light in the closet so that I can see even hints of the other things in there when the LED is off then I can actually keep staring at the LED's position.
I believe this phenomenon is due to saccades [1]. Our eyes normally jump around randomly when we are looking at things. We can override that and force ourselves to stare at a point. My guess is that we need some reference in the field of view to focus our attention on to be able to do an override.
I'd guess that this same effect could happen with a blinking object in a dark sky.
If the lights on the things are blinking, I have a possible explanation for the erratic motion.
I've found that if I'm in a dark place with a green LED that is blinking and there is not enough light to see anything but the LED then the LED appears to jump around erratically.
I'll see it come on and go off and I'm sure that I am continuing to stare at the now off LED but when it comes on it is somewhere else. If I'm about 40 cm from the LED it can appear to have jumped up to maybe 15-20 cm.
It can be quite disconcerting if there is a series of apparent jumps in the same direction, because each time I have to move my eyes/head in the same direction to recenter the LED, and after 4 or 5 jumps it feels like I should be turned significantly but I can tell that I'm actually still looking mostly straight ahead.
If I arrange for their to be some faint light in the closet so that I can see even hints of the other things in there when the LED is off then I can actually keep staring at the LED's position.
I believe this phenomenon is due to saccades [1]. Our eyes normally jump around randomly when we are looking at things. We can override that and force ourselves to stare at a point. My guess is that we need some reference in the field of view to focus our attention on to be able to do an override.
I'd guess that this same effect could happen with a blinking object in a dark sky.
[1] https://en.wikipedia.org/wiki/Saccade