Blue Orb Reappears at Exact Same Spot

At Grand Central Terminal in New York I took the photo on the left on June 9, 2016, and I took the photo on the right on June 16, 2016. Both show an identical-looking blue orb, and in both photos the orb seems to be in exactly the same position. On both days I took lots of other photos of the same window, none of which showed this orb.