Roswell's official city slogan is "We Believe" but I suspect what most Roswell residents believe is that tourist dollars are good, rather than anything about aliens. The alien myth has been a major economic boon to the city.
https://www.krqe.com/news/new-mexico/roswell-unveils-new-com...
How did you judge the distance of a silvery oval in the sky? We're generally pretty bad at estimating distance without sufficient cues (https://www.sciencedirect.com/science/article/pii/0042698979... https://psycnet.apa.org/record/1997-02284-005 https://www.nature.com/articles/35102562). It may have been something smaller and closer than you thought, and so not necessarily making insane movements.
> Either this is psychological and people have some kind of built-in hallucination effect for this specific phenomena in the sky
It doesn't have to be "built-in" - suggestibility could play a big role.
Whenever someone says it was "as big as a ..." or "impossibly fast", they're usually interpreting what they actually saw through their faulty intuition about those things. Angular size like the OP said is a useful observation, but not actual size.
I experienced this the first time I flew on a plane. I was watching the clouds passing by just below the plane and had a feeling for our comfortable speed, then suddenly a whispy bit of cloud in the foreground shot past much faster than I thought we were travelling and gave me a little shock. I then realized the clouds I'd been watching were probably much further away than I'd imagined.
Even if it was close by, you don't jump from almost stationary to the other side of the sky from your perspective at a reasonable speed.
https://i.ibb.co/ryNRd9C/2021-04-26-07-15-41.jpg
https://i.ibb.co/zXZRp5B/2021-04-26-07-15-34.jpg
Edit: photos has not been altered other than iOS auto resizing.
It just "hanged" there for about 20 minutes and then vanished. Did not move at all, did not change the lighting.
I hear that the crashes were shoot-downs or Trojan horse style gifts designed to lure us into co-operation with ETs who sly gave us tech far too advanced for us to figure out, then promised to slowly teach us how some of it works in exchange for whatever cooperation. There's lots of narrative and can be argued both ways, but without people seeing some hard data they believe, probably we'll have zero consensus.
I did hear a stereotypically UFO hovering sound a few minutes later even though there was nothing anywhere around me.
Either this is psychological and people have some kind of built-in hallucination effect for this specific phenomena in the sky. Which is interesting and should be studied. Or it's the real thing. And if it's real it's not going to affect our life by any amount unless we want it to. If the aliens wanted to land and share information or anything else with us they would have done it already, and we can't force them to do any such thing so who cares.
I am also extremely skeptical of Roswell type claims of crashed craft, unless the aliens have horrible QA engineers or we get millions of visitors per century I doubt they would crash one of their flying cars on our planet.