Unexplained marks on comet photographs in Allery

Summary

In March 1996, an astronomy enthusiast in Allery photographed a comet and discovered strange black marks on the images that he could not explain. The low quality of the photographs prevented any conclusive analysis. Despite his knowledge in the field, the witness was unable to determine the origin of these anomalies. The official investigation could not provide a definitive answer either, and GEIPAN classified the case as C, with no clear explanation.