Visibility III / V
I really don't know if this sighting should be reported as aurora borealis, night clouds or even a rocket launch? Maybe all of these would do, but the northern lights were still the most important performer of the evening. Quite an explosive beginning of the northern lights season indeed. The dark blue moment was only enough for a couple of hours. As typically happens in photography, I missed the best moments before I could stretch myself out into the yard. Here are some bad raps from the night's special encounter. Of course, the clouds got in the way before I could photograph anything. At first I thought these night cloud-like "night clouds" were ordinary night clouds, but I have seen and photographed natural night clouds many times, and this case was somehow strikingly different. The night clouds were also limited to a very small area, in the northeast direction. Their color was visually more white than blue. I agree with the speculation here about a possible nocturnal cloud-like remnant caused by a rocket launch.
P.S. The last two depict "ordinary" northern lights and clouds colored by street lights.
The pictures are not in exact chronological order.