Giant Silk Moth
A pair of Giant Silk Moths resided on our front porch by the light for a week or so and then moved on to wherever Giant Silk Moths go. They are so pretty. Their scientific name is Polyphemus. Bill Welch (the Bulb Baron at www.BilltheBulbBaron.com ) identified it for me. Wikpedia describes the moth as having a 6-inch wingspan and purple eyespots on hindwings . The caterpillar eats 86,000 times it's weight in less than two months.