From the Ghost Blog: What is an Orb?

Tom and Rob are official investigators in the Inspired Ghost Trackers group, and we've been on several investigations over the last year. We recently investigated an old mill turned art colony. In some photos, orbs appeared, which led me (Rob) to write the following blog on my ghost book blog:

What is an Orb?

Recently a friend from Florida sent me a photo of an orb that appeared in a photo taken outside his house. What's interesting is that he's had paranormal activity in his house -including footsteps, movement of doors and objects, and he's seen shadow figures. So, I sent the photo to the Inspired Ghost Trackers of Maryland to analyze it.
   That leads me to this week's blog: What is an orb? 
Wikipedia says: Orb (optics), an unexpected, often circular photographic artifact
- I've noticed orbs appear in photos whenever I'm sensing a ghost. Orbs are a simple form of light, and may or may not be the entity.
  There were several instances when orbs have appeared in photos when I sense a ghost nearby. In Riversdale Mansion, Riverdale, Md. I sensed a woman and a little girl in a large room. At the time, one of the members from Inspired Ghost Trackers was taking photos, and in one of them, several orbs appeared in front of a window.
  During a private investigation, I sensed a lot of emotional energy and distress in a furnace room that turned out to be where two women were murdered. In a follow-up investigation days later, an orb appeared with the face of a woman behind it! (It will be in my 2nd book coming later in 2012 called "Lessons Learned from the Dead.").
   So, what do others say about orbs? 

Orbs appear in Riversdale Mansion room when I sensed 2 ghosts.

Dave Juliano of Shadowland.net, a ghost hunter, defines an Orb this way: The orb is the energy being transferred from a source (i.e. powerlines, heat energy, batteries, people, etc) to the spirit so they can manifest.   This may not even be a conscious thing the spirit is doing, just a natural way they get their energy.  This would explain why the orbs are round balls.  According to the laws of Physics energy being transferring like that would assume is natural shape of a sphere.   This theory can also be tied into the EMF readings we get during spirit activity. Source: http://theshadowlands.net/ghost/orbs.htm
   Dave brings up a good point about Camera Processing errors: The digital cameras can't have film-processing errors.  I am aware that some people feel that the orbs on a digital camera are an error in the digital processing of the image.  When that error does occur in digital photos, the objects tend to be square in nature, not round and they cannot be semi-transparent, the pixel behind would have to be corrupted also.