Sunspot??

After watching a NOVA program on PBS tonight about the sun I was reminded of this photograph I took in Florida in March. I wish I would have had something interesting to frame in this amazing foggy sunrise over the Everglades but there was nothing nearby. I was photographing wildlife at sunrise on the 10,000 Islands Marsh Trail and by the time I could walk to find something to  compose in the photo this light would have been long gone. An interesting thing about this photograph is the black speck on the sun, at first I thought it looked like dust in my camera but then I discovered it was on all the photos in the exact same place on the sun. Dust in the camera would be in different places as I composed the photo differently. Anyone know if it is possible to have a sunspot show up on a photograph??