Science cannot explain the tilma, to this day.
There is no under sketch, no sizing and no protective over-varnish on the image. Microscopic examination revealed that there were no brush strokes. The image seems to increase in size and change colors due to an unknown property of the surface and substance of which it is made. According to Kodak of Mexico, the image is smooth and feels like a modern day photograph. Produced 300 years before the invention of photography.) The image has consistently defied exact reproduction, whether by brush or camera. Several images can be seen reflected in the eyes of the Virgin. It is believed to be the images of Juan Diego, Bishop Juan de Zummaraga, Juan Gonzales-the interpreter and others.The distortion and place of the images are identical to what is produced in the normal eye, which is impossible to obtain on a flat surface. The stars on Our Lady's Mantle coincide with the constellation in the sky on December 12, 1531. All who have scientifically examined the image of Our Lady over the centuries confess that its properties are absolutely unique and so inexplicable in human terms that the image can only be supernatural.
Altogether 24 popes have officially honored Our Lady of Guadalupe. His Holiness Blessed John Paul II visited her Sanctuary four times: on his first apostolic trip outside Rome as Pope in 1979, and again in 1990, 1999 and 2002.