The crater at Haleakala, Maui. Just after sunrise. I was taking a series of sequential pictures to put together for a panoramic picture. Starting at the left side of the crater and going to the right side of the crater. I took three shots taking a total of 13 seconds to complete the series of shots. When I reviewed the pictures I noticed a spot on all three shots. I thought I had dust on my lens. I checked my lens and cleaned it. I took three more shots and when I reviewed them no spots.When I got home from our vacation, I downloaded all of our pictures into my computer and started to select the ones I wanted to print and frame. When I was selecting the ones from Haleakala, I remembered the spots and looked at the pictures carefully. That's when I noticed the spot wasn't in the same area of the picture it was moving across the picture, which proved to me it wasn't a dust particle and the last shot there was a trail. As if it was moving very fast and away from me. I checked the shutter speed and it was 1/1307. I figured that, for what ever it was to leave a trail at that shutter speed it had to be moving very fast. A lot faster than a jet.Of course I showed a lot of people the pictures, in sequence and tried to explain the spots movement and everyone laughed at me.I have attached the pictures. Maybe someone can shed some light as to what it was I caught that morning.