Silly Saturday: UFO!

It was such a beautiful day today but, since I'm in this knee immobilizer, I couldn't go for a walk or bike ride.  I decided that it was a perfect excuse to sit out on the deck in the sun with a good book.  As I was reading, I heard fluttering wings and looked up.  Lucky that I had my camera nearby so I could capture this strange bird/insect that was flying over.  I have searched the internet and all my nature books but I haven't been able to identify it.  Please feel free to help with the ID....

Thanks to Admirer for hosting Silly Saturdays and for her lovely comments every week.  :-))