I came home tonight to find a piece of glass missing from my window, but it wasn't a break-in. Help me figure out the cause.
I live in a ground-floor flat facing onto a busy residential street, fairly safe neighbourhood, and came home at about 11pm to find my window has a tiny hole in it (about 1.2m off the ground) and a chunk of glass missing behind that.
The glass turned up about 1.5m back from the window, and it's like a flattish hemisphere, about the size of my thumbnail in diameter. I can see a very small line of refraction outside the window but no real cracking, no sign of the surface being damaged beyond.
There's no sign of a break-in, nothing outside the window I can see, and there were no crazy fluctuations in temperature or, I don't know, nail storms today - I've been out since early morning, though.. I will have to notify my landlord but I'd love to have some clue of what happened first.
Photos of the piece of glass: 1
Please help, mystery solvers!