Winged visitor

A little beauty came to visit. Actually, it was a big beauty. You can't tell very well from the picture, but this moth was a good five inches across. It was about to die (you can see how the edges of its wings are drying). I'd never seen such a large moth live (just in museums and on TV and whatnot). I watched it in the doorway, then shooed it out, figuring it would die there and then maybe I could keep it? But the next morning when I went to look, it was gone. Either crawled off to die somewhere else or was eaten by something else.