History of the Western Calendar

Transcription

1 History of the Western Calendar Plus an Introduction to other calendars: 1) Eastern Orthodox 2) Islamic 3) Jewish John Gavin CLS Winter 2018 The Times They Are A-Changing 1

2 Outline Day 1 Calendar: keeping track of days, months and years Julian and Gregorian Calendars Day 2 Roman Catholic and Eastern Orthodox Easter George Washington s Birthday Eastern Orthodox Holy Days Day 3 Islamic Lunar Calendar Jewish Solar & Lunar Calendar The Times They Are A-Changing 2

3 Calendars Attempts to rigorously create an approximation of the movement of the sun and moon Very old calendars are amazing accurate Calendars try to precisely nail down religious holy days All calendars are approximations The exact dates of most religious holy days are announced by experts and few people understand how they are calculated The Times They Are A-Changing 3

4 If I offend anyone or make mistakes It is by accident and out of ignorance. This could happen when discussing religions that I am not a member of. Details in this presentation could be slightly incorrect. This subject is poorly defined on the internet. I had to go the Poughkeepsie Public Library and consult the Encyclopedia Britannica. UTUBE videos about calendars are amazing awful The Times They Are A-Changing 4

5 The Times They Are A-Changing 5

6 Part I: Introduction The Times They Are A-Changing 6

7 How I Got Interested Year 2000 panic (Y2K) George Washington had many different birthdays February 11, 1732 Old Style with New Year on January 1 February 22, 1732 New Style February 11, 1731/2 Dual Dating The October or Bolshevik Revolution in Russia Occurred on October 25, 1917 And was celebrated on November 7, 1918 Determining the dates for: Roman Catholic Easter Eastern Orthodox Easter Ramadan Passover The Times They Are A-Changing 7

8 *** Key: Our Ancestors View *** It is easy to observethe following events Day: sunrise to sunrise Month: new moon to new moon Year: sun at highest point in the sky With great effort our ancestors created amazingly accurate measurementsfor these events. These ancient estimates are still good enough for everyday life But very small errors add up over hundreds or thousands of years Modern technology allows for very precise measurements that were impossible until recent technological advances. The Times They Are A-Changing 8

9 A Complex Statement Today is Thursday September 28, 2017 The Times They Are A-Changing 9

10 Complex Statement Today is Thursday September 28, 2017 Thursday Named after the Norse god Thor: ThorsDay. Thursday is the fifth day of a seven day week. The Times They Are A-Changing 10

11 Complex Statement Today is Thursday September 28, 2017 Thursday Named after the Norse god Thor: ThorsDay. Thursday is the fifth day of a seven day week. September The name of a the 9th month of our 12 month calendar year. Confusingly Septem is Latin for Seven, not Nine The Times They Are A-Changing 11

12 Complex Statement Today is Thursday September 28, 2017 Thursday Named after the Norse god Thor: ThorsDay. Thursday is the fifth day of a seven day week. September 28 The name of a the ninth month of our twelve month calendar year. Septem is Latin for Seven or Seventh. the 28 th day in the month of September which has 30 days Thirty days hath September, April, June and November The Times They Are A-Changing 12

13 Complex Statement Today is Thursday September 28, 2017 Thursday Named after the Norse god Thor: ThorsDay. Thursday is the fifth day of a seven day week. September The name of a the ninth month of our twelve month calendar year. Septem is Latin for Seven or Seventh. the 28 th day in the month of September which has 30 days Thirty days hath September, April, June and November 2017 is the approximate number of years since the birth of Christ, so more accurately it is 2017 AD (Anno Domini) or 2017 CE (Common Era), if you are using the our Western calendar. The Times They Are A-Changing 13

14 Names of the Days of the Week The Times They Are A-Changing 14

15 Week For some reason humans have been grouping days into weeksfor a long time. The Biblical God created the universe in six working days and he rested on the seventh. Fourth Commandment: Exodus 20:8-11 Definition: One Week = 7 Days You need a new calendar every year because 365 divided by 7 equals 52 with 1 left over It is very difficult to know what day of the week it was on July 4, 1776 The Times They Are A-Changing 15

16 Days of the Week Roman Name (Latin) English French German Heavenly Object 1 diēs Sōlis Sun day Dimanche: Sonn tag Sun Lord s Day 2 diēs Lūnae Mon day Lundi Mon tag Moon 3 diēs Martis Tues day Mardi Diens tag Mars 4 diēs Mercuriī Wednes day Mercredi Mittwoch Mercury 5 diēs Iōvis Thurs day Jeudi Donners tag Jupiter 6 diēs Veneris Fri day Vendredi Frei tag Venus 7 diēs Saturnī Satur day Samedi: Sams tag: Saturn Sabbath Sabbath The Times They Are A-Changing 16

17 Our Days of the Week English Sun day Mon day Tues day Wednes day Thurs day Fri day Satur day Derrivation Sun Moon Tiw: One Handed Norse God of single combat Woden: the Germanic god Woden Thor: the Norse god of Thunder Frige: Anglo-Saxon goddess Saturn: original Roman name: the god Saturn The Times They Are A-Changing 17

18 *** Key: Three Types of Calendars *** Solar: based on the sun Our calendar is based on the sun Lunar: based on the moon Islamic Calendar is 100% Lunar Lunar / Solar Combination Jewish Calendar Month based on the moon Year based on the sun Quite complicated The Times They Are A-Changing 18

19 Part II The Julian Calendar Essentially the calendar we use today The Times They Are A-Changing 19

20 *** Key: Three Types of Calendars *** Solar: based on the sun Our Western calendar is based on the sun Lunar: based on the moon Islamic Calendar is 100% Lunar Lunar / Solar Combination Jewish Calendar Month based on the moon Year based on the sun Quite complicated The Times They Are A-Changing 20

21 March: 31 day Julian month. Slightly differnet for non 31 day months 1 Kalends of March New Moon days before Kalends of April 2 5 days before nones days before Kalends 3 4 days before nones days before Kalends 4 3 days before nones days before Kalends 5 2 days before nones days before Kalends 6 1 day before nones days before Kalends 7 Nones of March days before Kalends 8 7 days before ides 23 9 days before Kalends 9 6 days before ides 24 8 days before Kalends 10 5 days before ides 25 7 days before Kalends 11 4 days before ides 26 6 days before Kalends 12 3 days before ides 27 5 days before Kalends 13 2 days before ides 28 4 days before Kalends 14 1 day before ides 29 3 days before Kalneds 15 Ides of March Full Moon 30 2 days before Kalends 31 1 days before the Kalends of April Years were normally named: The sixth year of the reign of Emperor Johannes Gavinus The Times They Are A-Changing 21

22 The Old Roman Calendar before 150 BC Latin Meaning Length English 1 Mensis Martius Mars: God of War 31 March 2 Mensis Aprilis Latin "aperire": to Open 29 April 3 Mensis Maius Maia: Fertility Godess 31 May 4 Mensis Iunius Juno: Marriage Goddess 29 June 5 Mensis Quintilis Fifth Month 31 July 6 Mensis Sextilis Sixth Month 29 August 7 Mensis September Seventh Month 29 September 8 Mensis October Eighth Month 31 October 9 Mensis November Ninth Month 29 November 10 Mensis December Tenth Month 29 December 11 Mensis Ianuarius Latin "ianua": Door 29 January 12 Mensis Februarius Latin "februum": Purification 28 February Total Days 355 Note: January and February were added at the end of the year at some unknown time Days were added to keep the year somewhat in synch with the sun. Latin had no "J", so Maia could be Maja and Iunius would be Junius. The Times They Are A-Changing 22

23 *** Julian Calendar: January 1, 45 BC *** English Latin Meaning Length French 1 January Mensis Ianuarius Latin "ianua": Door 31 janvier 2 February Mensis Februarius Latin "februum": Purification 28 février 3 March Mensis Martius Mars: God of War 31 mars 4 April Mensis Aprilis Latin aperire: "to open" 30 avril 5 May Mensis Maius Maia: Fertility Goddess 31 mai 6 June Mensis Iunius Juno: Marriage Goddess 30 juin 7 July Julius Caesar Fifth later named after him 31 juillet 8 August Emperor Augustus Sixth later named after him 31 août 9 September Mensis September Seventh Month 30 septembre 10 October Mensis October Eighth Month 31 octobre 11 November Mensis November Ninth Month 30 novembre 12 December Mensis December Tenth Month 31 décembre Total Days 365 Notes: 1) Every fourth year February has 29 days (Leap Year with 366 days) 2) The Year, averaged over 4 years, is days long (365 days and 6 hours) The Times They Are A-Changing 23

24 *** Ancient Estimations *** - Julian Calendar - Solar Year: our ancient ancestors observed the movement of the sun and counted the days until it returned to its highest point in the sky days is the length of the Julian year when the year is averaged over four years. Published in 45 BC daysis the length of the average Solar yearas calculated by modern instruments. 11 ¼ minutes per year: this is how much longer per year the 2,000 old Julian estimate is from the modern astronomical estimate. 11 minutes and 15 seconds Pretty darn good. The Times They Are A-Changing 24

25 Problems with the Julian Calendar Julian Calendar worked very well for a long time The Julian calendar fell behind the sun 1 day in 128 years or minutes per year The Julian calendar was a little too long (too slow) You d hardly notice in a lifetime But the minutes per year error really adds up in 1500 years. The numbers don t calculate exactly, but by 1582 AD the Julian calendar was ten days behind the sun. This was very important because the date for Easter was critically important to Roman Catholics in Using the wrong date was sacrilegious. The Times They Are A-Changing 25

26 AD vs. BC -One More Complication - The Times They Are A-Changing 26

27 Just to Confuse Matters Even More -AD vs. BC - Made Up, Arbitrary Definition Started on March 25, 1 AD Year started on March 25: The Annunciation Christmas Is nine months later. This dating system was devised in 525 by Dionysius Exiguus of Scythia Minor, but was not widely used until after 800. AD = Anno Domini: year of the Lord: aka CE: Common Era BC = Before Christ: akabce = Before the Common Era No Year zero year: 1 BC is followed by 1 AD All dates had to be retrofitted into AD or BC Makes you wonder how many historic dates are inaccurate PS: Julius Caesar created the Julian Calendar in 45 BC (Before Christ) Mr. Caesar didn t know it was 45 BC. He never heard of it. Christ wasn t even born yet The Times They Are A-Changing 27

28 Gregorian Calendar - The Calendar We Use in the USA - The Times They Are A-Changing 28

29 The race from 45BC to 1582 AD Julian Calendar 1600 years later October 4, 1582 October 14, 1582 The Sun 1600 solar years later Problem: Julian calendar takes 11 minutes and 15 seconds longer to get to each year s finish line. It is slower. By 1582 the Julian Calendar was 10 days behind the sun. The Times They Are A-Changing 29

30 How to fix the Julian Calendar One Time Fix Skip ten calendar days to allow the Julian Calendar to catch up with the Solar Cycle The day after October 4, 1582 became October 15, 1582 Ongoing Fix : change leap year rules a little Small correction:remove 72 hours every 400 years. About 11 minutes per year Remove three leap years every 400 years in century years not divisible by not a leap year 1800 not a leap year 1900 not a leap year 2000 was a leap year with a February 29 The Times They Are A-Changing 30

31 October 1582 Calendar In Roman Catholic Italy, France, Spain and Portugal The Times They Are A-Changing 31

32 Solution: How to Fix The Julian Calendar Julian 1627 years later October 4, 1582 Need to skip days on calendar to catch up Oct 15 The Sun s date 1627 years later, if the sun was using its own calendar October 14, 1582 Oct 15 Catch Up: the calendar had to jump ahead ten days to catch up with the sun. The day after October 4, 1582 became October 15, Fix the calendar rules: drop three leap years every 400 years. This keeps the updated calendar in synch with the sun. This Updated Julian Calendar is called the Gregorian Calendar. Named after Pope Gregory XIII, who was in charge in Very confusing for the peasants, Protestants and Orthodox Catholics. The Times They Are A-Changing 32

33 Unintended Consequence Chaos: October 4 still was followed by October 5, 1582 in Protestant Europe and Eastern Orthodox world On the English side of the English Channel it was October 5 Julian and on the French side it was October 15 Gregorian. Calendars probably not very important to most people 500 years ago The Times They Are A-Changing 33

34 Calendar Accuracy In Days Average Solar year Average Julian year A little too long. over 4 yrs Average Gregorian year A tiny bit too long. over 400 years The Julian calendar falls behind the Solar Year by one day in 128 Years The Gregorian calendar falls behind the Solar Year by one day every 3,030 years. Could correct this by making the year 4000 a common or non-leap-year The Times They Are A-Changing 34

35 Personal Editorial In reality we are still using the Revised or Updated or New Style Julian Calendarwith three leap years removed every 400 years: It was scientifically farsighted of Pope Gregory to go out on a limb and make the necessary changes. But the political timingwas bad because only a few countries accepted the updated calendar Italy, France, Spain and Portugal Other countries wanted nothing to do with anything Papal The Times They Are A-Changing 35

36 The Pope s Power in 1582 Why the Gregorian Calendar had customer acceptance problems The Times They Are A-Changing 36

37 The Pope s Management Problems - Eroded Power Base by 1582 AD AD: Constantine made the Catholic Church the official religion of the entire Roman Empire. Roman Pope became powerful. 330 AD: Constantine moved the capital of the entire Roman Empire (West and East) to Constantinople Roman Pope lost influence and the East became independent Circa 500 AD: The Fall of Rome and the Western Roman Empire. The Roman Pope was living in chaos, but the German tribes were already Arian Christians and later became Roman Catholics AD: East West Schism of 1054 AD. The Roman Pope excommunicated the entire Eastern Orthodox Catholic Church. An East-West split along old East / West Roman Empire lines to 1650 AD: Protestant Reformation: Luther, Calvin, Henry VIII and others. A North-South split in Western Europe The Times They Are A-Changing 37

38 After the Fall of Rome 526 AD The Times They Are A-Changing 38

39 East West Schism 1054 AD The Times They Are A-Changing 39

40 Protestant Reformation Results: 1600 AD The Times They Are A-Changing 40

41 The Pope s Management Problems - Eroded Power Base by 1582 AD AD: Constantine moved the capital of the entire Roman Empire (West and East) to Constantinople Circa 500 AD: The Fall of Rome 1054 AD: East West Schism of 1054 AD 1517 to 1650 AD: Protestant Reformation The Times They Are A-Changing 41

42 Our Calendar Year in Review - Very Arbitrary and Very Accurate - We are really using a slightly updated Julian Calendar 2,000 years later. Based on an rough estimate of the birth of Jesus. 400 Year Cycle of Leap Years 7 months with 31 days, 4 months with 30 days One month February has 28 days except in years evenly divisible by four, it has 29, except when it is a century year that is not divisible by , 1800 and 1900 were not leap years, but 2000 was. Our calendar started as a Religious / Scientific calendar and has become a global Civil Calendar The Times They Are A-Changing 42

43 Part III Julian and Gregorian Oddities Roman Catholic Easter Eastern Orthodox Easter The Times They Are A-Changing 43

44 Incorrect formula for getting the date of Easter I always thought that Roman Catholic Easter was based on astronomical observations of the Spring Equinox and the next Full Moon. Our ancestors knew that the date and time of the equinox is different at different locations or it could be cloudy. The Times They Are A-Changing 44

45 Setting the Date for Roman Catholic Easter - A Moveable Feast - 1. Vernal Equinox: fixed date of March The Full Moon after the Equinox: Look up the date in a 19 Year table of Ecclesiastical Full Moons. If the Equinox and the full moon both occur on March 21, that s ok. Write down the date of the full moon and figure out the day of the week. o You need a calendar to do this or very complex formulas 3. Easter Sunday: o If the Full Moon occurs on Monday through Saturday, then the upcoming Sunday is Easter. o If the Full Moon occurs on a Sunday, then you have to wait a full week for the following Sunday which is Easter. The Times They Are A-Changing 45

46 Pascal (Easter) Full Moon Table 2018 divided by 19 = 106 with remainder 4 Julian Gregorian Both The Times They Are A-Changing 46

47 Easter 2018: Roman Catholic G for Gregorian Roman Catholic Easter: Gregorian Calendar March 21, 2018 (G): Vernal Equinox, date set by RC Church March 31, 2018 (G): the next Gregorian Ecclesiastical Full Moon Date found in Gregorian column ( ) of table Then check the 2018 Gregorian calendar to find the day of the week (Saturday) or use very complex rules. Sunday April 1, 2018 (G): Easter Sunday The Times They Are A-Changing 47

48 Easter 2018: Eastern Orthodox Julian Calendar now 13 days behind the sun J is for Julian Eastern Orthodox Easter: Julian Calendar March 21, 2018 (Julian): Vernal Equinox Orthodox Church also uses a set date, but a different calendar March 22, 2018 (J): the next Julian Ecclesiastical Full Moon Look up date in Julian column of table Then check Julian calendar to find the day of the week (Wednesday) or use very complex rules Orthodox Easter is Sunday March 26, 2018 (Julian) But they use a different calendar The Times They Are A-Changing 48

49 Easter 2018: Roman Catholic and Orthodox Dates - The Two Calendars Make All The Difference - Roman Catholic Easter: Gregorian Calendar Roman Catholic Easter: Sunday April 1, 2018 (Gregorian) Eastern Orthodox Easter: Julian Calendar Orthodox Easter: Sunday March 26, 2018 (Julian) Converts to Sunday April 8, 2018 (Gregorian) Like most complicated concepts, the date for Roman Catholic and Eastern Orthodox Easter is announced by religious experts. The Times They Are A-Changing 49

50 Roman Catholic Easter Earliest: In 1818 the Vernal Equinox and the Paschal Full Moon both fell on Saturday March 21 (G). The next day was a Sunday Easter was on March 22, 1818 (G) This will not happen again until 2285, a span of 467 years. Latest:In 1943 the Vernal Equinox occurred as usual on March 21, but the next Pascal Full Moon did not happen until Sunday, April 18. Since the full moon was on Sunday you had to wait until the following Sunday for Easter Easter was on April 25, 1943 (G) Easter will not fall as late again until 2038, a span of 95 years. The Times They Are A-Changing 50

51 Part IV Julian and Gregorian Oddities - George Washington s Birthday - October November Bolshevik Revolution - The Times They Are A-Changing 51

52 Confusion The Protestant England refused to use the Papist Gregorian Calendar, so they continued to use the Julian Calendar until 1752, 170 years later. When England did adopt the new calendar they called it The New Style Calendar OS Old Style Julian NS New Style very similar to Gregorian George Washington was born on all of these dates: February 11, 1731: Old Style with New Year on March 25 February 11, 1732: Old Style with New Year on January 1 February 11, 1731/2: Dual Dating hedging your bets February 22, 1732: New Style with New Year on January 1 The Times They Are A-Changing 52

53 George Washington s Birth Record - Dual Dating - Hard to see, but it says that George was born on 11 th Day of February 1731/2 March 25 was legally New Year s Day March 25 is the Feast of the Annunciation: The Angel Gabriel announces that Mary is miraculously impregnated and nine months later Jesus is born (December 25) Most people used January 1 as New Year s day. The Times They Are A-Changing 53

54 The calendar problem in Virginia 1. Legally New Year s Day was March 25 One Time Fix: Remove 82 days at the end of 1751, so that New Year s Day 1752 would be January 1, England continued to use the Julian Calendar and by 1752, the Julian calendar was 11 days behind the solar cycle. One Time Fix: Skip September 3 14 in And like all Julian calendars, the Leap Year rules were slightly incorrect Ongoing Fix: Drop 3 leap years every 400 years & 1900 are not be Leap Years, but 2000 is The Times They Are A-Changing 54

55 English Legal Year: 1750 Old Style # Month Dates Days 1 March 25th to 31st 7 2 April 1st to 30th 30 3 May 1st to 31st 31 4 June 1st to 30th 30 5 July 1st to 31st 31 6 August 1st to 31st 31 7 September 1st to 30th 30 8 October 1st to 31st 31 9 November 1st to 30th December 1st to 31st January 1st to 31st February 1st to 28th March leftover 1st to 24th 24 Total Days 365 The Times They Are A-Changing GW was 19 on Feb 11, 1750

56 English Legal Year: 1751 Transition Year # Month Dates Days 1 March 25th to 31st 7 2 April 1st to 30th 30 3 May 1st to 31st 31 4 June 1st to 30th 30 5 July 1st to 31st 31 6 August 1st to 31st 31 7 September 1st to 30th 30 8 October 1st to 31st 31 9 November 1st to 30th December 1st to 31st January 1st to 31st 0 12 February 1st to 28th, plus leap 29th 0 13 March leftover 1st to 24th GW has no birthday in 1751 The Times They Are A-Changing 56

57 English Legal Transition Leap Year 1752 # Month Dates Days 1 January 31 2 February 29 3 March 31 4 April 30 5 May 31 6 June 30 7 July 31 8 August 31 9 September Skip 11 days October November December 31 Total Days 355 GW was 20 on Feb 11, 1752 Skip 11 days In September The Times They Are A-Changing 57

58 The Times They Are A-Changing 58

59 English New Style Year 1753 # Month Dates Days 1 January 31 2 February 28 3 March 31 4 April 30 5 May 31 6 June 30 7 July 31 8 August 31 9 September October November December 31 Total Days 365 GW was 21 on Feb 22, 1753 The Times They Are A-Changing 59

60 George Washington s Birthday Born on February 11, 1731 Old Style (Julian) with New Year on March 25 Born on February 22, 1732 New Style with New Year on January 1 George is almost one year younger in calendar gibberish The Times They Are A-Changing 60

61 Same Story at a Later Date The October or Bolshevik Revolution occurred on October 25, 1917 Julian November 7, 1918 Gregorian Russia did not adopt the Gregorian Calendar as their civil calendar until after the Russian Revolution By 1918 the Julian calendar was 13 days behind the sun. Wednesday January 31, 1918 (Julian) was followed by Thursday February 14, 1918 (Gregorian) And three leap years every 400 years are dropped. The Russian Orthodox Church never adopted the Gregorian calendar. The Times They Are A-Changing 61

62 Part V Julian and Gregorian Oddities - Eastern Orthodox Holy Days - The Times They Are A-Changing 62

63 East West Schism 1054 AD The Times They Are A-Changing 63

64 Eastern Roman Empire (aka Byzantine Empire) Lasted for almost 1,000 years after the Fall of Rome East West Schism in 1054 AD. The Roman Pope excommunicated the Eastern Catholic Church Roman Catholic Church Western Europe; Centered in Rome; Latin language. Eastern Orthodox Catholic Church Eastern Europe and Middle East; Centered in Constantinople; Greek language. Orthodox Catholics are 100% independent of Rome The Times They Are A-Changing 64

65 Autocephalous (reports to no one) Orthodox churches - in Full Communion with each other - 1. Constantinople: sort of the senior bishop. Many other independent churches report into Constantinople. 2. Alexandria 3. Jerusalem 4. Russia 5. Serbia 6. Romania 7. Bulgaria 8. Georgia 9. Cyprus 10. Greece 11. Poland 12. Albania 13. Czech lands and Slovakia 14. America There are many other branches: Communion of True Orthodoxy, Old Believers (Old Ritualists), excommunicated churches, Oriental Orthodox Churches, etc The Times They Are A-Changing 65

66 Religious Differences - Back to the calendar - The Council of Nicaea (325 AD) modern Turkey There was only one Catholic Church in the entire Roman Empire (West and East) The method for setting the date for Easter was set at the Council using the Julian Calendar. In 1054 AD the Roman Catholic Pope excommunicated the Eastern Orthodox Catholic Church In 1582 Roman Catholic Pope Gregory XIII updated the calendar and created the Gregorian Calendar The Eastern Orthodox Church continues to use the Julian Calendar as true believers in the Council of Nicaea. Nicene Creedis read at every Roman Catholic Mass The Times They Are A-Changing 66

67 Two Types of Orthodox Holy Days Fixed feasts occur on the same calendar date every year 1. Most Orthodox Churches, including Russian Orthodox, use the Julian Calendar Christmas is on December 25 Julian (January 7 Gregorian) In 2102 Christmas will be January 8 Gregorian as Julian calendar continues to slip behind. 2. Greek, Cyprus and Romanian Orthodox Christmas is on December 25 Revised Julian / Gregorian Movable feasts: dates change every year Pascha (Easter) is a Moveable Feast, All Orthodox Churches use the Julian calendar to calculate Easter. The Times They Are A-Changing 67

68 Russian vs. Greek Orthodox Holy Days Russian Orthodox (Julian) Christmas: Dec 25 Julian January 7 Gregorian Annunciation: Mar 25 Julian April 7 Gregorian Greek Orthodox (mixed) Christmas: Dec 25 Revised-Julian December 25 Gregorian Annunciation: Mar 25 Revised- Julian March 25 Gregorian Easter: based on Julian Same in all Orthodox Churches Easter:based on the Julian Same in all Orthodox Churches The Times They Are A-Changing 68

69 Pascal (Easter) Full Moon Table 2018 divided by 19 = 106 with remainder 4 Julian Gregorian Both The Times They Are A-Changing 69

70 Easter 2018 Roman Catholic Easter 2018 divided by 19 equals 106 with remainder of 4. Look in full moon table: Pascal Full Moon: March 31 Gregorian Find a 2018 Gregorian calendar: March 31 is a Saturday So the next Sunday is Easter on April 1, 2018 Gregorian Eastern Orthodox Easter (Russian Orthodox) 2018 divided by 19 equals 106 with remainder of 4. Look in full moon table: Pascal Full Moon is March 22 Julian Find a 2018 Julian Calendar: March 22 is Wednesday Wed 22 nd, Thurs 23 rd, Friday 24 th, Sat 25 th, Sun 26 th So the next Sunday is Easter on March Julian March 26 Julian converts to Sunday April 8, 2018 (Gregorian) Eastern Orthodox Easter (Greek Orthodox) Same date as Russian Orthodox except converted to Gregorian Sunday April 8, 2018 Gregorian The Times They Are A-Changing 70

71 ***A Rose By Any Other Name *** - The Julian Calendar - Julian Calendar: used by Eastern Orthodox Churches Revised Julian Calendars: Gregorian Calendar: used by Roman Catholic Church and as the almost world wide civil calendar. Revised Julian Calendar: used by Greece, Cyprus and Romania Orthodox Churches for Fixed Feast Days New Style Calendar: United Kingdom (UK) It would have been much easier if the updated Gregorian Calendar was called the Revised Julian Calendar. The Times They Are A-Changing 71

72 Part VI - Islamic Lunar Calendar - The Times They Are A-Changing 72

73 *** Key: Three Types of Calendars *** Solar: based on the sun Our calendar is based on the sun Lunar: based on the moon Islamic Calendar is 100% Lunar Lunar / Solar Combination Jewish Calendar Month based on the moon Year based on the sun Quite complicated The Times They Are A-Changing 73

74 *** Ancient Lunar Estimations *** Islamic Lunar Month:Islamic astronomers counted days from new moon to new moon and created an approximate measurement of the length of the lunar month. Each month starts when the lunar crescent is first seen (by a human observer s eye) after a new moon. Basic Islamic Lunar Month was estimated to be 29.5 days, which is an excellent approximation. Islamic Lunar Month averaged over a 30 year cycle with 11 leap days is days Modern Astronomical figure: days The average Islamic year over the 30 year lunar cycle lags behind the astronomical lunar cycle by less than 5 minutes per year. Wow!!!!! The Times They Are A-Changing 74

75 Islamic Months No. Name Meaning Note 1 Muḥarram forbidden All unlawful acts (violence) are forbidden. 2 Ṣafar void 3 Rabī al-awwal the first spring The Prophet Muhammad was born in this month. 4 Rabī ath-thānī the second spring 5 Jumādá al-ūlá the first of parched land 6 Jumādá al-ākhirah the last of parched land 7 Rajab respect, honour Fghting is forbidden. 8 Sha bān scattered 9 Ramaḍān burning heat Muslims fast from pre-dawn till sunset and should give charity to the poor and needy. 10 Shawwāl raised 11 Dhū al-qa dah the one of truce / sitting People used to stop their business and stop war and prepare for the Hajj (Pilgrimage). 12 Dhū al-ḥijjah the one of pilgrimage Muslim pilgrims from all around the world congregate at Mecca. Fighting is forbidden. Note: many of the month names refer to the seasons in the arid desert, but the lunar calendar does not hold to these cycles. Perhaps they were the seasons when the calendar was defined. The Times They Are A-Changing 75

76 Islamic Lunar Year Basic Islamic Lunar Year is 354 days long six 29 day months and six 30 day months 29.5 times 12 equals 354 Islam is not concerned that their religious calendar is not in synch with the solar year or our Western solar calendars or even the civil calendar they use Islamic Lunar Year falls behind our the astronomic Solar Calendar Year by days per solar year Islamic Lunar Year falls all the way back through the Gregorian Solar Year in about 32.5 solar years. The Holy Month of Ramadan can be any date on our Western Solar calendar. The Muslim faithful don t care that Ramadan is a moveable date, as Jews and Christians aren t bothered by Passover and Easter moving around. The Times They Are A-Changing 76

77 2036 The Times They Are A-Changing 77

78 Islamic Calendar The Islamic, Muslim, or Hijri calendar is a lunar calendar consisting of 12 months in a year of 354 days. There are 11 leap years (355 days in a leap year) in their 30 year calendar lunar cycle. The Islamic calendar uses the Hijri era (622 AD) as Year 1 for counting their years. In 622 AD Muhammad and his followers migrated from Mecca to Medina The current Islamic year is 1439 AH which runs from Sept 21, 2017 to September 10, 2018 Gregorian. Ramadan is the 9th month of Islamic calendar, the month that the Quran was revealed. Ramadan is a month of fasting. First day of Ramadan: May 16, 2018 The lunar month seems complicated because we talk about it using our Solar days and years. Like most complicated concepts the date of Ramadan is announced by religious experts. The Times They Are A-Changing 78

79 In the astronomical-lunar-calendar system Astronomical Lunar Year: days long (12 astronomical lunar months) Astronomical Lunar Month: days. Islamic Lunar Year: 354 days. Islamic Lunar Month: days Difference: 0.03 days or 0.72 hours or 43.2 minutes This leaves only a small monthly variation of 44 minutes to account for, which adds up to a total of 24 hours (i.e., the equivalent of one full day) in 2.73 years. To settle accounts, it is sufficient to add one day every three yearsto the lunar calendar, in the same way that one adds one day to the Gregorian calendar every four years. The Times They Are A-Changing 79

80 Islamic Calculations: amazingly accurate Astronomy Islamic Calculations days in an Islamic Lunar Month times lunar months per year days in an Islamic Lunar Year times years in the Islamic calendar cycle ,620 days in 30 Islamic lunar years 11 plus leap days added in 30 years 10,631.0 days in 30 year lunar cycle and leap days Finally -10,631.0 Thirty Astonomical Lunar Years are one tenth of a day longer than the Islamic 30 year cycle (about 2.4 hours) The Times They Are A-Changing 80

81 Our Western Difficulty Understanding the Islamic Lunar Calendar We insist on comparing it to our solar calendar Islamic Lunar Year Astronimical Solar Year days days days Diff hours Lunar minus solar Islamic Lunar Year is days short of solar Year Takes 32.5 Solar Years for any Islamic lunar date to cycle back to same solar day Years The Times They Are A-Changing 81

82 Islamic Calendar Summary Leap days are added to keep the Islamic Lunar Calendar in synch with the Astronomical Lunar calendar. This had nothing to do with the astronomical solar calendar or Julian or Gregorian. There are 11 leap years in a 30-year cycle. Their distribution varies slightly from one country or Muslim community to another. However, the most common version defines the 2nd, 5th, 7th, 10th, 13th, 16th, 18th, 21st, 24th, 26th, and 29th year of each 30-year cycle as leap years. Leap day added to the last month of the year. Takes about 33 years for Ramadanto move backwards through the year. Makes fasting very difficult the farther you get away from the equator The Islamic world doesn t care about the Gregorian calendar for religious celebrations Just like Easter and Passover don t care about the Gregorian or Julian solar calendars. They are determined by both the Sun and the Moon. The Times They Are A-Changing 82

83 Part VII - Hebrew Lunar / Solar Calendar - The Times They Are A-Changing 83

84 *** Key: Three Types of Calendars *** Solar: based on the sun Our calendar is based on the sun Lunar: based on the moon Islamic Calendar is 100% Lunar Lunar / Solar Combination Jewish Calendar Month based on the moon Year based on the sun Quite complicated The Times They Are A-Changing 84

85 How Hebrew Calendar Works The Hebrew calendar s Year 1 is Creation This year is 5778 AM (Anno Mundi), which started at sundown Wednesday September 20, 2017 G and will end on September 9, 2018 G Lunar Calendar: The monthsfollow the movement of the moon and average 29.5 days. One Lunar Year equals Twelve lunar months. Normal Jewish lunar year has about 354 days (29.5 times 12). The Astronomical Lunar Year is days So the Jewish lunaryear is 0.37 days (9 Hours) shorter than the astronomical lunar year. Reconciling to the Solar Year Astronomical Solar or Tropical Year is days Jewish defined Lunar year is 354 days Jewish Lunar Year is days shorter than the Solar Year. This is exactly the same as the Islamic Lunar calendar. But the Jews wanted to bridge this gap. How? The Times They Are A-Changing 85

86 # Month Normal Year in Days 1 Tishri 30 Normal Jewish Year Short Year in Days Long Year in Days 1 Tishri is Rosh Hashanah, 10 Tishri is Yom Kippur Can add a day 2 Marcẖeshvan Kislev Can remove a day 4 Tevet 29 5 Shvat 30 6 Adar 29 7 Nisan Nissan is Passover 8 Iyar 29 9 Sivan Tammuz Av Elul The Times They Are A-Changing 86

87 # Month Normal Leap Year in Days Jewish Leap Year Short Leap Year in Long Leap Year in 1 Tishri 30 First month of civil year. 2 Marcẖeshvan Can add a day 3 Kislev Can remove a day 4 Tevet 29 5 Shvat 30 6 Adar I* Leap Month Added Here 7 Adar / Adar II* The real Adar, also known as Adar II 8 Nisan 30 Nisan 1 is the Ecclesiastical New Year 9 Iyar Sivan Tammuz Av Elul The Times They Are A-Changing 87

88 Hebrew Calendar Regular Year: 12 months or 354 days Can be 353 days: remove 1 day from 9 th Month Can be 355 days: add 1 day to the 8 th Month Leap Year: 13 months or 384 days But it can also be 383 or 385 days long The adding or removing of one day is done to prevent important holy days from occurring on the wrong day of the week Jewish New Year: Civil Year: begins on Rosh Hashanah (Tishrei 1) Religious Year: begins on Nissan 1 opassover is Nissan 15 to 22. The Times They Are A-Changing 88

89 How Hebrew Calendar Works: Dig Deeper Solar Calendar:But the Jews wanted to keep their calendar in synch with the sun,so an extra 30 day leap-month is added every two or three years. Leap Year is about 384 days long in the 3rd, 6th, 8th, 11th, 14th, 17th, and the 19th years of the 19 year cycle Butany year can have one extra day or one fewer day so that religious holy days don t interfere with each other. A normal year can have 353, 354 or 355days A leap year can have 383, 384 or 385 days. Must ensure that Passover is celebrated in the spring. From Internet: There are exactly fourteen different patterns that the Hebrew calendar years may take, distinguished by the length of the year and the day of the week on which Rosh Hashanah falls. Because the rules are complex, a pattern can repeat itself several times in the course of a few years, and then not recur again for a long time. I can t do the exact math because I can t figure out which years have a day added or a day removed. Complex but only loses a day to the sun every 216 solar years (or so I ve read). The Times They Are A-Changing 89

90 Hebrew 19 Year Solar Cycle is NOT Enough Cycle Year Days Astronomical Year days years Total 6, days <====> 6, days Difference Jewish calendar is 3.6 days shorter over 19 year cycle But there's still another tweak The Times They Are A-Changing 90

91 Many Jewish New Years 1 Tishrei: the anniversary of creation. (Sept 21, 2017 G). National Holiday of New Year in Israel. Fall. 15 Shevat: the New Year for trees (Jan 31, 2018 G). Marks the beginning of a new year for trees. This is the season in which the earliest-blooming trees in the Land of Israel emerge from their winter sleep and begin a new fruitbearing. Winter is beginning to break. 1 Nisan: the season of the redemption from Egypt and the birth of the Israelite nation. (March 17, 2018 G). Almost Spring. 1 Elul: the New Year for the tithing of cattle. Tax Day. (Aug 12, 2018 G) Elul is a time of repentance in preparation for the High Holy Days of Rosh Hashanah and Yom Kippur. Late Summer. The Times They Are A-Changing 91

92 Additionally Dates of Jewish holidays do not change from year to year on the Hebrew Calendar Holidays are celebrated on the same day of the Jewish calendar every year, but the Jewish year is not the same length as a solar year or the Gregorian calendar used by most of the western world, so the date shifts on the Gregorian calendar. In addition, Yom Kippurshould not fall adjacent to a Sabbath, because this would cause difficulties in coordinating the fast with the Sabbath, and Hoshanah Rabbashould not fall on Saturday because it would interfere with the holiday's observances. A day is added to the month of Heshvan or subtracted from the month of Kislev of the previous year to prevent these things from happening. The Passover begins on the 15th day of the month of Nisan, which typically falls in March or April of the Gregorian calendar, typically begins on the night of a full moon after the northern vernal equinox. However, due to intercalary monthsor leap months falling after the vernal equinox, Passover sometimes starts on the second full moon after vernal equinox, as in The Times They Are A-Changing 92

93 List of All Holiday Dates Below is a list of all major holiday dates for five years. All holidays begin at sundown on the day before the date specified here. Rosh Hashanah /3/2016 9/21/2017 9/10/2018 9/30/2019 9/19/2020 Yom Kippur 10/12/2016 9/30/2017 9/19/ /9/2019 9/28/2020 Sukkot 10/17/ /5/2017 9/24/ /14/ /3/2020 Shemini Atzeret Simchat Torah 10/24/ /12/ /1/ /21/ /10/ /25/ /13/ /2/ /22/ /11/2020 Chanukkah 12/25/ /13/ /3/ /23/ /11/2020 Tu B'Shevat 2/11/2017 1/31/2018 1/21/2019 2/10/2020 1/28/2021 Purim 3/12/2017 3/1/2018 3/21/2019 3/10/2020 2/26/2021 Pesach (Passover) 4/11/2017 3/31/2018 4/20/2019 4/9/2020 3/28/2021 Lag B'Omer 5/14/2017 5/3/2018 5/23/2019 5/12/2020 4/30/2021 Shavu'ot 5/31/2017 5/20/2018 6/9/2019 5/29/2020 5/17/2021 Tisha B'Av 8/1/2017 7/22/2018 8/11/2019 7/30/2020 7/18/2021 The Times They Are A-Changing 93

94 Passover: a moveable holy day The new moon starts the Jewish month and the full moon occurs in the middle of the month Religious leaders identify the new moon that falls after the Fall Equinox (September 21). That new moon is in late September or early October New moon is Tishrei 1 (Rosh Hashanah) Beginning of civil calendar The seventh month is Nissan Passover begins at sunset of Nissan 15 (After the Fall Equinox) The Times They Are A-Changing 94

95 *** Passover and Christian Easter *** Passoverand Easterare closely linked in the Christian New Testament Jesus celebrated Passoveron Holy Thursday, died the next day on Good Friday and rose from the dead on Easter Sunday. Eastern Orthodox Church insists that Passover comes before Easter. Western Christian Churches do not insist on this Biblical chronology In 2024 Passover is on April 22, 2024 G and Easter is on March 31, 2024 G The Times They Are A-Changing 95

96 *** Excellent Estimate *** Hebrew calendar year is longer by about 6 minutes and 40 seconds than the current mean tropical year, so that every 216 years the Hebrew calendar will fall a day behind the current mean tropical year An expert must announce these dates since it is too complicated for the rest of us The Times They Are A-Changing 96

97 Part VIII - Time and Seasons - The Times They Are A-Changing 97

98 Big Modern Question: When was the universe created? This has nothing to do with the Jewish calendar. Maybe? When I was in Catholic elementary school in the Bronx, I remember a religion book (from the 1930s) with a timeline that showed the earth was about 6,000 years old. This idea is alive and well with creationists. James Usher ( ), the Anglican Primate of All Ireland and a noted scholar calculated that Creation started on 1 Anno Mundi (year of the earth). Saturday October 22, 4004 BC Julian. Adam and Eve were driven from Paradise later in 1 Anno Mundi Monday November 10, 4004 BC Julian. Paradise for 19 days. Noah s Ark touched down on Mount Ararat in 1656 AM Wednesday May 5, 2348 BC Julian This year would be about 6022 Anno Mundi Or 2018 AD The Times They Are A-Changing 98

99 Complex Statement It is 11:55 AM in Poughkeepsie, New York. It is Winter. Eastern Standard Time AM: Ante Meridiem, before midday PM: Post Meridiem, after midday (ends in EM ) 11:59 AM is followed by 12:00 PM Note: there is another similar, but different word: Meridian (in AN ) A prime meridianis a meridian (a line of longitude) which is defined to be 0 Longitude. Example: Greenwich Meridian in England. It is winter. The days are short. New York is in the Northern Hemisphere The earth s axis is tilted 23.5 degrees The Winter Solstice occurred around December 21 The Times They Are A-Changing 99

100 The Times They Are A-Changing 100

101 Seasons The first accurate, modern, western observations of the obliquity (tilt of 23.5 degrees) were probably those of Tycho Brahe from Denmark, about The Times They Are A-Changing 101

102 Four Seasons Earth s axis at 23.5 degrees. See diagram Applies in mid-latitudes, not equator or poles Special Astronomical Events (Northern Hemisphere) Winter Solstice (aka midwinter) is usually on or near December 21 marks the day with the shortest period of daylight and the longest night of the year. Vernal Equinox: usually March 20 Equal day and night Summer Solstice: usually June 21 (aka midsummer) marks the day with the longest period of daylight and the shortest night of the year Autumnal Equinox: usually September 22 Equal day and night The Times They Are A-Changing 102

103 Universal Time: date and time of equinoxes and solstices on Earth Equinox Solstice Equinox Solstice March June September December Year Date Time Date Time Date Time Date Time : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : :02 The Times They Are A-Changing 103

104 Weeks, Days and Hours Week: 7 days A 365 day year has 52 weeks plus 1 extra day Day: an easy concept. For example the time from one sunset to the next sunset Dayis a unit of timethat is divided arbitrarily into 24 hours. Hour: base 12 number system 1 12 of the nighttime or 1/12of the daytime.night and day vary by season, latitude, and weather. 1 Day = 24 Hours = 1,440 minutes = 86,400 seconds Note the base 12 number system 1 Year = 12 Months = 1 x 12 months 1 Day = 24 hours = 2 x 12 Hours 1 Hour = 60 minutes = 5 x 12 Minutes 1 Minute = 60 seconds = 5 x 12 Seconds Circle = 360 degrees = 30 x 12 degrees The Times They Are A-Changing 104

105 Has It Ever Confused You 11:59 PM is followed by 12:00 AM (Midnight) 11:59 AM is followed by 12:00 PM (Noon) All arithmetic taught you not to change the unit of measure. It s just a definition. The Times They Are A-Changing 105

106 Part IX - Final Words - The Times They Are A-Changing 106

107 Complex Statement #1 Today is Thursday September 28, 2017 Thursday Named after the Norse god Thor: ThorsDay. Thursday is the fifth day of a seven day week. September The name of a the ninth month of our twelve month calendar year. Septem is Latin for Seven or Seventh. the 28 th day in the month of September which has 30 days Thirty days hath September, April, June and November 2017 is the approximate number of years since the birth of Christ, so more accurately it is 2017 AD (Anno Domini) or 2017 CE (Common Era), if you are using the our Western calendar. The Times They Are A-Changing 107

108 Complex Statement #2 It is 11:55 AM in Poughkeepsie, New York. It is Autumn. Eastern Daylight Savings Time AM: Ante Meridiem, before midday 11:59 AM is followed by 12:00 PM It is autumn. The days are getting shorter. New York is in the Northern Hemisphere The earth s axis is tilted 23.5 degrees The Autumnal Equinox occurred a few days ago The Times They Are A-Changing 108

109 Calendar Name Type Cycle Description Rationale Julian / Old Style Solar Calendar 4 year 3 Solar common years and 1 Solar leap year Keep Julian Solar Calendar in synch with astonomical Solar observations Gregorian / New Style Solar Calendar 400 year 303 Solar common years and 97 Solar leap years Keep Gregorian Solar Calendar in synch with astonomical Solar observations Islamic 100% Lunar 30 year 19 Lunar common Keep the Islamic Lunar Calendar years years and 11 Calendar in synch with Lunar leap years astronomical Lunar observations Hebrew Lunar / Solar Calendar 19 year 12 Lunar common years and 7 Lunar leap years Keep the Hebrew Lunar Calendar in synch with astronomical solar observations. Solar is Red / Lunar is Blue The Times They Are A-Changing 109

110 Final Summary Year and Month are easy to observe and estimate, but it is impossible to measure them with great accuracy without modern technology A very small error really adds up over hundreds and thousands of years The Julian Calendar (Solar or Sun) was only adjusted three days (72 hours) every 400 years to create the Gregorian Calendar. Julian Calendar was published in 45 BC The Islamic LunarCalendar and the Hebrew Lunar/Solar Calendars are also amazingly old and amazingly accurate. These calendars were a great achievement for humankind. The more you know, the better they get. PS: there are a zillion other calendars. The Times They Are A-Changing 110

111 The End The Times They Are A-Changing 111