Most mysterious Orbs are actually bugs at night. They are sometimes attracted by the IR LEDs, that illuminate the area in front of the camera to provide a better Night Vision video, heat from the camera, and even the reflections off your camera's lens.
But generally these Orbs move about. If yours is stationary, then it could be the Night Vision picking up some type of reflection off some surface, causing a "Lens Flare" (some nearby light can cause a reflection in the lens itself). As a matter of fact, I noticed that your picture displays a pretty well lit area, and your camera has not even switched into the Night Mode (because you can still see color instead of the grayish display). Maybe illuminated from a overhead porch light? Try experimenting and turn off the porch light (and other lights) one-by-one and you may solve the mystery that is causing your Orb. Your picture looks more like a "Lens Flare" than bugs, especially if you notice your Orb is always in the same place each night (another link, concerning "Lens Flares"):