This is a crop of a possible meteor which was caught across two 15 second exposure captures. Since meteor flashes are brief, it must have happened right at the end of the first capture and into the second. Failing that, perhaps it was a tumbling satellite that only reflected light for a few seconds across both frames. The GIF animation further down the page shows each capture and then combined image. I could trace any known satellite in that part of the sky - 09-09-17