Very hard to tell without being able to see the face of the wings; the body suggests a type of silk moth, family Saturniidae, perhaps that just emerged and its wings are not fully inflated yet. Maybe try searching BugGuide or Google the family name and search by images.

Looks more like a Saturniidae, a silk moth member....perhaps Antheraea polyphemus?

Haha, I could have sworn that florafau suggested a sphinx moth on Tuesday!