These were visible in the sky all over the SF Bay Area today.
They apparently aren't all that unusual, but I'd never heard of them until today. (My reality just got a little bigger!)
https://en.wikipedia.org/wiki/Fallstreak_hole
They apparently aren't all that unusual, but I'd never heard of them until today. (My reality just got a little bigger!)
https://en.wikipedia.org/wiki/Fallstreak_hole