A Day on Torrance Creek Greenway

I spent the morning with a photographer friend, Tom Dills, on Torrance Creek Greenway out in Huntersville, NC. I have visited several of the Mecklenburg County greenways and this is certainly a very nice one. While on the greenway, you can actually forget that you are really very close to a thriving community and major streets. Very peaceful and teeming with wildflowers, birds, butterflies, deer (although I didn't see any today). It was interesting that folks walking or running on the greenway would often stop and ask us what we were photographing and often assumed we were photographing deer. I think these greenways are definitely a plus for Mecklenburg county and citizens. While there we saw this "butterfly" which appears to have 4 wings. I tried to find it in my reference books but the closest I can get is that of an "Imperial Moth". Is this correct? Have you seen such a beautiful creature before?