tribute of light

Damon and I just got back from NYC where we witnessed the "Tribute of Light" exhibit in memory of the disaster 3 years ago. We were amazed at the sparkles appearing in the lights. It was breathtaking, and somewhat surreal. We were in the West Village, so it was a bit too far away to determine what exactly the sparkles were, but we supposed that they were birds or bats caught in the beams.

I found an article about this on Gothamist, which seems to confirm that they were indeed birds.

Panorama views by Jook Leung  |  Space Cannon - the lighting designers