In fact, it might be that their method is a lot lot simpler: - Detect any protracted images on the photos which shouldn't be protracted - Interpret ends of th

In fact, it might be that their method is a lot lot simpler: - Detect any protracted images on the photos which shouldn't be protracted - Interpret ends of them as 2 observations and dots at 1/3 and 2/3 as 2 others (exploiting the fact that speed of angular motion at such a short interval is essentially constant). - Run a (very crude) orbit detection using these - Look for any suspicious dots on other images within the margin of error provided by this orbit (that is, where the object with that orbit should've been if it was real, at a time each other shot was made). - If found, use these for orbit refinement, rinse and repeat until on all shots where the object should've been apparent, it is present, or reject it as a false detection if that doesn't happen.