Another Giant Purple Air Orb

Photo date: April 13, 2015. Photographer: Mark Mahin.

The following photo was taken in New York City. On the left we see a giant purple orb that took up 59% of the original photo height. Photos before and after showed no such thing.

An orb this size cannot be explained as a dust particle in front of the camera, as you would need something the size of a golf ball right in front of the camera to produce something this large, and dust particles in the air are never larger than about the period at the end of this sentence.  There was no precipitation on this night in New York City, and according to airnow.gov, the air quality was "good," with a rating of 34 (any number below 50 is classified as good).  This means the dust particle sizes on this night were no more than about 10 microns, but it would have required a particle of at least 10,000 microns to produce an orb such as this.

The photo was taken with a full-spectrum camera that also produced this set of photos showing a similar-looking giant purple air orb. The camera was not at all facing any bright light, so lens flare is not a plausible explanation.