Weird black object over Binghamton

On July 31, 2015, a witness was in Binghamton (Broom County, New York) and watched a hot air balloon launch. He took photo of this event. Later, he discovered a mysterious object in photo.

Witness statement:

I was taking pictures of a hot air balloon launch at a balloon rally. Later, when looking at my pictures I noticed and object in the sky that I didn't see while taking the photo. No one else noticed it that I know of at the time. I showed the picture to my son and he recommended that I send the photo to you.