I've just got in from watching owls. I was sitting at the computer with the window open and could hear faint rasping noises... Opening the window and leaning out, the noises were more audible and revealed the source to be a Barn Owl.
Looked down the road and, silhouetted against a beautiful sky, was a hunting owl, flapping gently - almost butterfly-like - and silently disappeared behind one of the barns.
It's one of those ultra-clear evenings where the sky goes through a gradient of deep blue (with stars) at the top, through orange and yellow to a dull, ashy brown where it hits the horizon.
It seemed too good to miss, so I went to stand outside in the garden. I couldn't see the owl, but I could hear it calling as it flew around in the dark. It's really hard to describe Barn Owl noises. They do vary a lot, but this one sounded almost insect-like, slightly whirring, a bit Nightjarry, maybe.