Back from the National Aviary!
They thought our project was interesting. I had four bird experts consulting, and the bird of prey expert was there.
We're definitely looking at the bird from the underside with its wings outstretched.
With certainty, it's not an eagle or a falcon.
It's either a Red Tail Hawk or a Great Horned Owl.
Most likely a Red Tail Hawk of Buteo Genus, but we shouldn't disregard Great Horned Owl entirely.
Here's why:
The pattern on the tail feathers is like a Great Horned Owl because it's a disorganized bark-like pattern.
Red Tail Hawk tail feather patterns are very clear defined lines and symmetrical.
They think it's an artist's inaccurate depiction of a Red Tail Hawk because you almost never see an owl flying and/or soaring with outstretched wings. (It's not that they don't/can't do it, it's just incredibly rare for someone to see them doing it.) Owls are most often seen sitting or diving with their wings forward. The only time you'd typically see an owl with its wings in this position is if it's taking off.
They say it's incredibly common to see a Red Tail Hawk in this position. It makes sense with a sun, not so much with a moon.
IMO, the reason we shouldn't disregard Great Horned Owl is because of how rare he says it would be to see it in this position. If we find artwork of an Owl with outstretched wings, it should be pretty darn easy to determine the origin because of its rarity.
But our focus shouldn't be only on the Great Horned Owl since it's highly unlikely.
Hope that makes sense!