An Orb in Super-Clean Air

Photo date: September 23, 2014.  Photographer: Mark Mahin.

To help rebut the theory that orbs are all caused by dust,  I electronically measured the dust level at a particular indoor location to be very low. I then took the photograph below, which shows a large, luminous orb. My electronic dust measurement device lists a dust level reading of less than 50 as being "very good" air, and the reading at the time was only 15, which is almost as low as you could get outside of a clean room.

Dust level: 15/2, Very Good: Reflective surfaces nearby: none. No orbs shown in photos taken at same location from same angle soon before and soon after this photo was taken, which argues against any dust explanation.