Friday the 13th one occurrence each. A Friday the 13th occurs during any month that begins on a Sunday. The fear of the number 13 has been given a scientific name: "triskaidekaphobia"; and on analogy to this the fear of Friday the 13th is called "paraskevidekatriaphobia", from the Greek words "Paraskeví" (Παρασκευή, meaning "Friday"), and "dekatreís" (δεκατρείς, meaning "thirteen"). The superstition surrounding this day may have arisen in the Middle Ages, "originating from the story of Jesus' last supper and crucifixion" in which there were 13 individuals present in the Upper Room on the 13th of Nisan Maundy Thursday, the night before his
Friday the 13th "Born in Blood: The Lost Secrets of Freemasonry", Dan Brown's 2003 novel "The Da Vinci Code" and Steve Berry's "The Templar Legacy" (2006). In Spanish-speaking countries, instead of Friday, Tuesday the 13th ("martes trece") is considered a day of bad luck. The Greeks also consider Tuesday (and especially the 13th) an unlucky day. Tuesday is considered dominated by the influence of Ares, the god of war ("Mars" in Roman mythology). The fall of Constantinople to the Fourth Crusade occurred on Tuesday, April 13, 1204, and the Fall of Constantinople to the Ottomans happened on Tuesday, 29 May 1453, events that