Periodic Comet Holmes (17P) erupted completely out of the blue in October 2007, which led to its spectacular appearance for the last two months of the year in the constellation Perseus.  This picture shows the comet just west of the cluster of stars around Mirfak, α Persei.  On this scanned slide, we can see the reddish nebulosity of the Heart and Soul Nebulae, the Double Cluster, and M34.  By this date, the comet was already taking on a diaphonous appearance, even though in this long-ish exposure, it appears to be solidly white.   Unannotated image.