How do the stars on the tilma of Our Lady of Guadalupe relate to the stars in the sky?
A viewer asks how the arrangement of stars on the tilma of Our Lady of Guadalupe relates to the actual stars in the night sky.
Answer
The tilma does not have every star in the sky, and the stars on it look evenly spaced, not equidistant the way real stars are scattered in different places. What you can tell is that the basic pattern of the stars on the tilma follows what you would have seen from the city in Mexico where Juan Diego was, on that very evening in 1510. The sky changes from year to year and century to century; we are farther from Polaris now than then, and you have the equinoxes and the precessions all occurring, so it is very complicated. But the sky of that particular night is basically what you see on the tilma. My paper is just a start, and others have done good work on it too.