You can see in the painting how the stars were aligned on Christmas 1692 in Petrovaradinski when the construction of the fortress tunnel began. There is the legend of the Maltese cross. According to the legend the Sirius, the Maltese Cross, the crosses of the towers of the two churches (Samostan Svetog Jurja, Crkva Svetog Apostola Pavla) and Polaris lie in a straight line. You can see this line in the painting.
What do you think it means?