ok I've seen this three times in the night sky.
first time nobody believed me.
second time me and a friend witnessed it out of the corner of our eye(s)
third time me and 2 friends were near the beach laying on the ground looking at the stars and we all witnessed it.
On all three accounts I was looking at the stars and I noticed a ring around a star shrinking. when it hit the star the ring grew rapidly and the star was dim.
this all happened within a 10 second time period.
Again; I've witnessed this happen 3 times in my life, twice with other witnesses so I know I am not crazy.
I asked if it was a supernova but people say that one that far away wouldn't be visible by the naked eye.
I want an expert opinion, what the heck did i witness?
please don't troll
please don't post negative comments
you an be positive and informative at the same time without being an asshole.

thanks