I went to my apartment Window and I saw two orange glowing orbs fly in a straight line from South to North directly over Washington Square Park. Buildings in the way didn't let me see them for long, but it was long enough to discern their features. They looked like the glass balls of lightning plasma you can buy at novelty shops, but only the outer edge effect of orange plasma that occurs when you put your hands on the glass (no electrical arcing inside). There was nothing inside of them, just a flickering orange glowing around the surfaces, mostly at the leading edge. I felt they were some unknown natural phenomenon. I'm not sure why I didn't go outside, but somehow I felt like I'd see them again. It was strangely comforting to see them, actually.