Swastika on roman army shields/gear

[john m roberts]

Carl Sagan, in his book "Comet," theorizes that the image of the swastika may have come from the appearance of a large comet venting gas from four spots on its surface. Since comets rotate it would appear as a spiral-armed swastika. As evidence he presents an ancient Chinese book on the interpretation of comets as omens, which shows just such a comet. He stresses that all the most ancient depictions of the swastika have curved arms, not angular. Those come later. Also, he notes that the symbol is widespread in the northern hemisphere even on different continents, but is unknown from the southern, arguing for a comet visible in the northern hemisphere only. It's an interesting proposition, anyway.