The Orb Looked Lit From Above, But There Was No Light Above It

Photo date: May 31, 2017. Photographer: Mark Mahin.

The photo below shows a mysterious orb I photographed at Grand Central Terminal in New York.

The orb has an odd "lit from above" look to it, as if it was being lit from some light above it.  But there was no light above it. The lights at Grand Central were all below it, as we can see in the photo below.  There are no lights on the green ceiling of Grand Central (except for a few tiny lights meant to look like individual stars).