Whilst at work at the Library today, John one of my work colleagues said casually "We've got one of those Hawk moths here" and I went outside and it was rather very precariously perched on the edge of the outside door jamb. I moved the Moth for its own safety, which was a very impressive Poplar Hawk Moth, onto the outside wall. This awakened it and it's wings started whirring and it flew up and away and safe! Poplar Hawk Moths are a common species which usually frequent Poplar & Sallow trees.
It was probably attracted to the outside wall of the Library by the white outside light which is on at night for security reasons. This is the second time I've seen this species of moth outside the Library, we had another exactly a year ago in the same spot!