Information about Friday The 13th

There is a superstition that a Friday occurring on the 13th day of any month is a day of bad luck in English, French, German, Polish, Bulgarian, Portuguese and Norwegian-speaking cultures around the globe.

Similar superstitions exist in some other traditions. In Greece, Romanian and Spanish-speaking countries, for example, it is Tuesday the 13th that is considered unlucky.

The fear of Friday the 13th is called paraskavedekatriaphobia, a word that is derived from the concatenation of the Greek words Παρασκευή, δεκατρείς, and φοβία, meaning Friday, thirteen, and phobia respectively; alternative spellings include paskevodekatriaphobia or paraskevidekatriaphobia, and is a specialized form of triskaidekaphobia, a phobia (fear) of the number thirteen.

History of Friday the 13th

No historical date has been verifiably identified as the origin of the superstition. Before the 19th century, although there is evidence that the number 13 was considered unlucky, and Friday was considered unlucky, there was no link between them. The earliest confirmed reference to Friday the 13th as an unlucky day is from 1880.^[1] However, an 1869 biography of Gioachino Rossini mentions a possible link between the two superstitions:

[Rossini] was surrounded to the last by admiring and affectionate friends; and if it be true that, like so many other Italians, he regarded Friday as an unlucky day, and thirteen as an unlucky number, it is remarkable that on Friday, the 13th of November, he died.^[2]

However, many popular stories exist about the origin of the concept:

• That the biblical Eve offered the fruit to Adam on a Friday, and that the slaying of Abel happened on a Friday (though the Bible does not identify the days of the week when these events occurred).^[3]
• The Last Supper which occurred on Thursday, with Judas numbered among the thirteen guests (Jesus plus his 12 apostles), and that the Crucifixion of Jesus' looking which occurred on a Friday. However, Judas was not actually present for the latter part of the meal.
• Friday and 13 were both sacred to the Norse goddess Freyja, so Friday 13th was especially sacred. Christians who wished to suppress her worship said the day was unlucky.
• Friday, October 13th, 1066 was the last day of the reign of the Saxon King Harold II. On this day, William, Duke of Normandy offered Harold the option of ceding the crown; Harold declined the offer. The Battle of Hastings took place the following day (Saturday, October 14th, 1066). Harold was slain and William took control of England.
• The Knights Templar were arrested on Friday October 13, 1307. The notion that this is the origin of the superstition was mentioned in the very popular work of fiction The Da Vinci Code.

Effects in people and cultures

"It's been estimated that [U.S] $800 or $900 million is lost in business on this day because people will not fly or do business they would normally do."^[4]

Some people are so paralyzed by fear that they are simply unable to get out of bed when Friday the 13th arrives. The Stress Management Center and Phobia Institute estimates that more than 67 million people are affected by a fear of this day.^[5] Despite that, representatives for both Delta and Continental Airlines say that their airlines don't suffer from any noticeable drop in travel on those Fridays.^[6]

A British Medical Journal study has shown that there is a significant increase in traffic-related accidents on Friday the 13ths.^[7]

Occurrence

The following months have a Friday the 13th: Month Years Dominical Letter January 2006, 2012, 2017, 2023 A, AG February 2004, 2009, 2015, 2026 D, DC March 2009, 2015, 2020, 2026 D, ED April 2001, 2007, 2012, 2018 G, AG May 2005, 2011, 2016, 2022 B, CB June 2003, 2008, 2014, 2025 E, FE July 2001, 2007, 2012, 2018 G, AG August 2004, 2010, 2021, 2027 C, DC September 2002, 2013, 2019, 2024 F, GF October 2006, 2017, 2023, 2028 A, BA November 2009, 2015, 2020, 2026 D, ED December 2002, 2013, 2019, 2024 F, GF

Or, the other way around, the following years have Friday the 13th's in these months: Dominical Letter Years Months A 2006, 2017, 2023 January, October B 2005, 2011, 2022 May C 2010, 2021, 2027 August D 2009, 2015, 2026 February, March, November E 2003, 2014, 2025 June F 2002, 2013, 2019 September, December G 2001, 2007, 2018 April, July AG 2012 January, April, July BA 2028 October CB 2016 May DC 2004 February, August ED 2020 March, November FE 2008 June GF 2024 September, December

Year Months 2001 April, July 2002 September, December 2003 June 2004 February, August 2005 May 2006 January, October 2007 April, July 2008 June 2009 February, March, November 2010 August 2011 May 2012 January, April, July 2013 September, December 2014 June 2015 February, March, November 2016 May 2017 January, October 2018 April, July 2019 September, December 2020 March, November

This sequence, here given for 2001–2028, repeats every 28 years from 1901 to 2099. The months with a Friday the 13th are determined by the Dominical letter (G, F, GF, etc.) of the year. Any month that begins on a Sunday will contain a Friday the 13th.

Every year has at least one and at most three Fridays the 13th, with 48 occurrences in 28 years (which is 336 months = 48 x 7 months), giving an average of 1.7 times per year, or once every 7 months. (Coincidentally, 336 is the 28th untouchable number.)

Patterns for non leap-years (if Friday the 13th occurs in the first month, it will also occur in later months) :

First month occurring	Second month	Third month
January	October
February	March	November
April	July
May
June
August
September	December

Patterns for leap years :

First month occurring	Second month	Third month
January	April	July
February	August
March	November
May
June
September	December	|October||||

The Gregorian Calendar 400-year cycle contains 146,097 days. Along with the 146,000 normal days, there are ninety-seven February 29's among them, (also called Leap Year Days). The easiest way to explain how and why the Gregorian Calendar rotates during any 400-year cycle is that there are 365 days every year. Ninety-seven of the 400 years are leap years, which have 366 days. Years with 365 days have 52 weeks, with one additional day; years with 366 days have 52 weeks, with two additional days. Adding the "additional days" over the 400-year period results in 497 total "additional days". These 497 days are exactly seventy-one weeks. Thus, the total number of weeks in the Gregorian Calendar cycle is 20,871. Because of this, no chosen day of the month up to the 28th can occur the same number of times on each day of the week. The 13th day of the month is slightly more likely to be a Friday than any other day of the week.^[8] On the average there is a a Friday the 13th once every 212.9 Days.

The distribution of the 13th day over the 4,800 months is as follows:

Day of the week	Number of occurrences
Sunday	687
Monday	685
Tuesday	685
Wednesday	687
Thursday	684
Friday	688
Saturday	684

There are 4,800 months in 400 years, so the 13th of the month occurs 4,800 times in this interval. The number of times the 13th occurs on each weekday is given in the table above. As shown by Brown (1933), the thirteenth of the month is slightly more likely to be on a Friday than on any other day.

Planned events on Fridays the 13th

Some events are intentionally scheduled for Friday the 13th for dramatic effect. They include:

• Black Sabbath's self-titled debut album was released in the UK on Friday, February 13, 1970.
• The 13th book of the Series of Unfortunate Events was released on Friday, October 13, 2006 by novelist Daniel Handler, also known as Lemony Snicket.

Natural events on Fridays the 13th

Due to the large number of negative events that happen in the world, a similar list could be compiled for any combination of day of the month and day of the week. Friday the 13th is also sometimes known as "Dooms day."

• The Uruguayan Rugby team infamously crashed in the Andes mountain range on Friday the 13th October, 1972
• January 13, 2006 and October 13, 2006 were not only Fridays, but the digits in the month, day, and year of each date add up to 13. This will next occur on May 13, 2011.
• Lake Storm "Aphid", an out-of-season snowstorm that wrought havoc on the Buffalo, New York area took place on Friday, October 13, 2006.
• The asteroid 99942 Apophis will make its close encounter on Friday, April 13, 2029.

Notable births and deaths

Born on Friday the 13th	Date of Birth
Oliviero de Fabritiis	13 June, 1902
Georges Simenon	February 13, 1903
Samuel Beckett	13 April, 1906
Bud Freeman	13 April, 1906
Sir Joh Bjelke-Petersen	January 13, 1911
Fred Daly	13 June, 1913
Eileen Farrell	13 February, 1920
Stuart Wagstaff	13 February, 1925
Jennifer Vyvyan	13 March, 1925
Margaret Thatcher	October 13, 1925
Fidel Castro	August 13, 1926
Herbert Ross	13 May, 1927
Rosalind Elias	13 March, 1931
Yuri Ahronovich	13 May, 1949
T. J. Cloutier	October 13, 1939
Carol Lynley	13 February, 1942
Zoë Wanamaker	May 13, 1949
Peter Davison	April 13, 1951
Max Weinberg	April 13, 1951
Deborah Raffin	13 March, 1953
Steve Buscemi	December 13, 1957
Julia Louis-Dreyfus	January 13, 1961
Will Clark	March 13, 1964
Tim Story	March 13, 1970
Michelle Sara Cox	December 13, 1974
Mary-Kate and Ashley Olsen	June 13, 1986
Marco Andretti	March 13, 1987
Desmond Wan	September 13, 1991

Died on Friday the 13th	Date of Death
Gioachino Rossini	November 13, 1868
Diamond Jim Brady	13 April, 1917
Arnold Schoenberg	July 13, 1951
Martita Hunt	13 June, 1969
Hubert Humphrey	January 13, 1978
Ralph Kirkpatrick	13 April, 1984
Benny Goodman	13 June, 1986
Gerald Moore	13 March, 1987
Stuart Challender	December 13, 1991
Tupac Shakur	September 13, 1996
Gary Jennings	February 13, 1999
Tony Roper	October 13, 2000

References

External links

• A Wikipedia Reading on Friday the 13th by: Quintin Barry(youtube.com)
• Friday the 13th Phobia Rooted in Ancient History
• Why Friday the 13th Is Unlucky (About.com)
• How Friday the 13th works (HowStuffWorks.com)
• National Geographic: Friday the 13th Phobia Rooted in Ancient History
• Friday the 13th and the Templars - About.com article
• Your Unlucky Day: The religious roots of triskaidekaphobia.
• Some don't count on Lucky 13 - Via Magazine.
• Paraskevidekatriaphobia - skepdic.com article on Friday the 13th
• http://www.infoplease.com/spot/friday13th.html
• A world of Luck: Friday the 13th - Snopes.com article
• Triskaidekaphobia on MathWorld