What broke my window?

Hard to say. The only reason you be so curious just to possibly avoid it in the future. The window was replaced today. Very easy now that they are using what is known as a D Seal gasket. No putty to mess with. However, it is a lesson with respect to double pane windows. They are much more expensive to replace and single pane. And apparently can’t be done by your local glass people. It was $350 for a replacement window! And that is only a 30 x 20 Item! It could’ve been a rock. But the small distinct hole makes me doubt that. BTW, i’ve discovered that a small, very inexpensive tool is sold that allows you to break the glass in your automobile window in case you are headed underwater. I saw one recently, and the rod that breaks the glass is about the size of the hole in the window. Just hold it to the window and push the button.