Hi, I think it is the phenomenon called "Noctilucent cloud".
They can be seen during twilights and they are the highest clouds in the earth's atmosphere, around 80 Km high. It is a recent discovery and they are still not very well understood.
But I am not 100% sure sorry, I am not a meteorologist, but I briefly studied them during my bachelor.
Cheers
Thanks mate! And if I may ask, what's your major?
major?
I meant, what did you do your bachelor's in?
Natural Science. Super broad but very interesting!
Yeah I'm sure I'll love it!