Mysterious Thing Near Empire State Building

Photo date: May 24, 2015.  Photographer: Mark Mahin.

The photo below shows some strange object above the Empire State Building in New York.

Below is a closeup of the object. If the "wings" of this object were shorter, we can suppose it's an insect or bird. But I know of no insect or bird with wings this long in relation to the thorax (with the possible exception of the dragonfly, which I can never recall seeing in New York City). For now I will vaguely label this using the label "miscellaneous luminous anomalies."