Had fun this morning looking at Joe's UFO photo. The 2 vertical stars to the right of and below Acamar are separated by about 3 degrees. The height of the UFO is thus about 3 degrees. Perusal of archived weather data for 15 Sept 2001 0700Z show rain on the W. Colorado/ E. Utah border about the latitude of Moab. Call the distance about 60 miles from The Wedge. That distance and angle give a height of 3.14 mi or 16600' agl, a reasonable height for a thunder head. Doubling the distance would double the height. Thunder cannot be heard for more than about 10 miles. A typical lightning rate is 3-5 per min. I count 15-20 dark 'dots' suggesting a 3 to 7 minute exposure time. Most of the 'dots' have vertical bars above them but not all. If the image is more or less full a 35 mm frame then the lens would appear to be about 50-60mm focal length from the coverage angle and frame size. If it was the 28m then the image must have been cropped. From the 'strobing' it would appear that the lighting was fairly regular and/or the storm didn't move much during the photo. Joe was on track by calling it thunder storm, I would agree that a T-storm is the most likely explanation. Steve