Spent much of its time hovering a foot off the ground.
My guide shows three different all-white tiger moths: Spilosoma latipennis, Spilosoma virginica, and Hyphantria cunea. I didn't try to view the underside for any markings there.
This pair seemed very interested in each other. Courtship?
Pair courting. The male (on the right) would vibrate his wings, and the female hopped around a bit.