What's the reason that we have different quantities of days each month?
$begingroup$
It always was interesting for me to understand the answer for the question:
What's the reason that we have different quantities of days each month?
If the month is fixed on the time that the moon circles the earth, then the time of the circling isn't equal each month? And if the month fixed by the time that the earth circles the sun and then divided by 12 (365:12=30.4), why one month has more days and the other month has less days?
Before desktop computers, how did astronomers handle calculations of dates and times accurately, for example two plates taken decades apart, how would an astronomer calculate the time difference precisely?
history time terminology
New contributor
$endgroup$
add a comment |
$begingroup$
It always was interesting for me to understand the answer for the question:
What's the reason that we have different quantities of days each month?
If the month is fixed on the time that the moon circles the earth, then the time of the circling isn't equal each month? And if the month fixed by the time that the earth circles the sun and then divided by 12 (365:12=30.4), why one month has more days and the other month has less days?
Before desktop computers, how did astronomers handle calculations of dates and times accurately, for example two plates taken decades apart, how would an astronomer calculate the time difference precisely?
history time terminology
New contributor
$endgroup$
$begingroup$
I've added an extra sentence to keep your question on-topic in Astronomy and not just about the history of calendars and how the month is defined for modern Gregorian calendars.
$endgroup$
– uhoh
5 hours ago
$begingroup$
only slightly related, calendar history/trivia in VSauce's How Earth Moves
$endgroup$
– uhoh
4 hours ago
add a comment |
$begingroup$
It always was interesting for me to understand the answer for the question:
What's the reason that we have different quantities of days each month?
If the month is fixed on the time that the moon circles the earth, then the time of the circling isn't equal each month? And if the month fixed by the time that the earth circles the sun and then divided by 12 (365:12=30.4), why one month has more days and the other month has less days?
Before desktop computers, how did astronomers handle calculations of dates and times accurately, for example two plates taken decades apart, how would an astronomer calculate the time difference precisely?
history time terminology
New contributor
$endgroup$
It always was interesting for me to understand the answer for the question:
What's the reason that we have different quantities of days each month?
If the month is fixed on the time that the moon circles the earth, then the time of the circling isn't equal each month? And if the month fixed by the time that the earth circles the sun and then divided by 12 (365:12=30.4), why one month has more days and the other month has less days?
Before desktop computers, how did astronomers handle calculations of dates and times accurately, for example two plates taken decades apart, how would an astronomer calculate the time difference precisely?
history time terminology
history time terminology
New contributor
New contributor
edited 5 hours ago
uhoh
5,90121661
5,90121661
New contributor
asked 5 hours ago
Ubiquitous StudentUbiquitous Student
1263
1263
New contributor
New contributor
$begingroup$
I've added an extra sentence to keep your question on-topic in Astronomy and not just about the history of calendars and how the month is defined for modern Gregorian calendars.
$endgroup$
– uhoh
5 hours ago
$begingroup$
only slightly related, calendar history/trivia in VSauce's How Earth Moves
$endgroup$
– uhoh
4 hours ago
add a comment |
$begingroup$
I've added an extra sentence to keep your question on-topic in Astronomy and not just about the history of calendars and how the month is defined for modern Gregorian calendars.
$endgroup$
– uhoh
5 hours ago
$begingroup$
only slightly related, calendar history/trivia in VSauce's How Earth Moves
$endgroup$
– uhoh
4 hours ago
$begingroup$
I've added an extra sentence to keep your question on-topic in Astronomy and not just about the history of calendars and how the month is defined for modern Gregorian calendars.
$endgroup$
– uhoh
5 hours ago
$begingroup$
I've added an extra sentence to keep your question on-topic in Astronomy and not just about the history of calendars and how the month is defined for modern Gregorian calendars.
$endgroup$
– uhoh
5 hours ago
$begingroup$
only slightly related, calendar history/trivia in VSauce's How Earth Moves
$endgroup$
– uhoh
4 hours ago
$begingroup$
only slightly related, calendar history/trivia in VSauce's How Earth Moves
$endgroup$
– uhoh
4 hours ago
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
You make a great point. The reason behind the discrepancy between the dates is due to a complicated history behind it.
The calendar is based on the calendar created by ancient Romans, which is based on one Moon cycle. One lunar cycle is
29.53 days.
www.universetoday.com/20620/lunar-year/
which does not evenly divide into the 365.25 days of the year.
Note: The Romans borrowed the calendar from the ancient Greeks to develop the idea of a 10-month calendar that left approximately 60 days unaccounted for.
Consequently, the earliest ancient Roman calendars had months that were either 29 or 30 days to account for this discrepancy.
The Romans started using the 10-month calendar in 738 B.C. that included Martius[March], Aprilis[April], Maius[May], Junius[June], Quintilis[July, quin- meaning "5"], Sextilis[August, sex- meaning "6"], September, October, November, and December.
To account for the remaining $pm60$ days, Januarius[January] was added to the beginning of the year and Februarius[February] to the end of the year during Numa's reign around 700 B.C with a leap year every 4 years. The calendar stayed in that order until 452 B.C. when a small council of Romans, called the Decemvirs, moved February to follow January.
However, people began adding a leap year every three years, so that caused a big problem. In fact, by the start of the reign of Julius Caesar, the previous calendar was off by a whole week!
Julius Caesar noticed this and thus modified the Roman calendar in 46 B.C. to make each month have either 30 or 31 days, with the exception of Februarius[February], which had 29 days, with the three year leap year fixed into a four year leap year, along with the nullification of a leap year when the year number is a multiple of 100. Quintilis[July] was later renamed Julius[July] in his honor. Likewise, Sextilis[August] later became Augustus[August] to honor Augustus Caesar, Julius' Aunt. Augustus[August] was also given an extra day (taken away from Februarius[February]), so that Augustus and Julius would have an equal number of days, representing their equal power.
This calendar was extremely accurate, but was still off as thousands of years later it was off by a day or so. Then a pope named Pope Gregory XIII modified the Julian calendar again in October 1582. This is the currently used Gregorian calendar. He made it so that
Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100, but these centurial years are leap years if they are exactly divisible by 400.
https://en.wikipedia.org/wiki/Gregorian_calendar
This calendar is the most accurate calendar there is, and won't be a single day off until the year of $pm 3500$ AD.
New contributor
$endgroup$
$begingroup$
There are some errors in this answer. Eg, before the adoption of the Julian calendar, leap years were decreed by proclamation the pontifex maximus, in such years an extra month was added to the calendar. In the Julian calendar, there is a leap day every 4 years (with no exception for century years), but in the initial 36 years of its adoption leap days were added every 3 years due to a misunderstanding (Romans used inclusive counting). See en.m.wikipedia.org/wiki/Julian_calendar#Leap_year_error
$endgroup$
– PM 2Ring
3 hours ago
$begingroup$
The Julian calendar drifts by approximately 3 days every 400 years. So after a few hundred years, not thousand years, the drift becomes noticeable (i.e. the seasons don't properly match the calendar), which is important for farming, and therefore human survival. The latest popular calendar, the Gregorian, drifts by about one day every 12000 years, if I remember correctly. Due to astronomical effects (the rotation of the Earth speeding up and slowing down, etc.) we can't be more precise than that. A calendar that's accurate today is extremely unlikely to be accurate in 12000 years' time.
$endgroup$
– CJ Dennis
2 hours ago
$begingroup$
@PM2Ring Ah I see. Are you able to edit that into my answer? I don't know enough to accurately type in what you said with an explanation. Perhaps may I quote you?
$endgroup$
– Max0815
10 mins ago
$begingroup$
@CJDennis I will fix this.
$endgroup$
– Max0815
10 mins ago
$begingroup$
@CJDennis its 3200 years for 1 day to be off. I checked in my notes from science class.
$endgroup$
– Max0815
2 mins ago
add a comment |
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1 Answer
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1 Answer
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oldest
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$begingroup$
You make a great point. The reason behind the discrepancy between the dates is due to a complicated history behind it.
The calendar is based on the calendar created by ancient Romans, which is based on one Moon cycle. One lunar cycle is
29.53 days.
www.universetoday.com/20620/lunar-year/
which does not evenly divide into the 365.25 days of the year.
Note: The Romans borrowed the calendar from the ancient Greeks to develop the idea of a 10-month calendar that left approximately 60 days unaccounted for.
Consequently, the earliest ancient Roman calendars had months that were either 29 or 30 days to account for this discrepancy.
The Romans started using the 10-month calendar in 738 B.C. that included Martius[March], Aprilis[April], Maius[May], Junius[June], Quintilis[July, quin- meaning "5"], Sextilis[August, sex- meaning "6"], September, October, November, and December.
To account for the remaining $pm60$ days, Januarius[January] was added to the beginning of the year and Februarius[February] to the end of the year during Numa's reign around 700 B.C with a leap year every 4 years. The calendar stayed in that order until 452 B.C. when a small council of Romans, called the Decemvirs, moved February to follow January.
However, people began adding a leap year every three years, so that caused a big problem. In fact, by the start of the reign of Julius Caesar, the previous calendar was off by a whole week!
Julius Caesar noticed this and thus modified the Roman calendar in 46 B.C. to make each month have either 30 or 31 days, with the exception of Februarius[February], which had 29 days, with the three year leap year fixed into a four year leap year, along with the nullification of a leap year when the year number is a multiple of 100. Quintilis[July] was later renamed Julius[July] in his honor. Likewise, Sextilis[August] later became Augustus[August] to honor Augustus Caesar, Julius' Aunt. Augustus[August] was also given an extra day (taken away from Februarius[February]), so that Augustus and Julius would have an equal number of days, representing their equal power.
This calendar was extremely accurate, but was still off as thousands of years later it was off by a day or so. Then a pope named Pope Gregory XIII modified the Julian calendar again in October 1582. This is the currently used Gregorian calendar. He made it so that
Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100, but these centurial years are leap years if they are exactly divisible by 400.
https://en.wikipedia.org/wiki/Gregorian_calendar
This calendar is the most accurate calendar there is, and won't be a single day off until the year of $pm 3500$ AD.
New contributor
$endgroup$
$begingroup$
There are some errors in this answer. Eg, before the adoption of the Julian calendar, leap years were decreed by proclamation the pontifex maximus, in such years an extra month was added to the calendar. In the Julian calendar, there is a leap day every 4 years (with no exception for century years), but in the initial 36 years of its adoption leap days were added every 3 years due to a misunderstanding (Romans used inclusive counting). See en.m.wikipedia.org/wiki/Julian_calendar#Leap_year_error
$endgroup$
– PM 2Ring
3 hours ago
$begingroup$
The Julian calendar drifts by approximately 3 days every 400 years. So after a few hundred years, not thousand years, the drift becomes noticeable (i.e. the seasons don't properly match the calendar), which is important for farming, and therefore human survival. The latest popular calendar, the Gregorian, drifts by about one day every 12000 years, if I remember correctly. Due to astronomical effects (the rotation of the Earth speeding up and slowing down, etc.) we can't be more precise than that. A calendar that's accurate today is extremely unlikely to be accurate in 12000 years' time.
$endgroup$
– CJ Dennis
2 hours ago
$begingroup$
@PM2Ring Ah I see. Are you able to edit that into my answer? I don't know enough to accurately type in what you said with an explanation. Perhaps may I quote you?
$endgroup$
– Max0815
10 mins ago
$begingroup$
@CJDennis I will fix this.
$endgroup$
– Max0815
10 mins ago
$begingroup$
@CJDennis its 3200 years for 1 day to be off. I checked in my notes from science class.
$endgroup$
– Max0815
2 mins ago
add a comment |
$begingroup$
You make a great point. The reason behind the discrepancy between the dates is due to a complicated history behind it.
The calendar is based on the calendar created by ancient Romans, which is based on one Moon cycle. One lunar cycle is
29.53 days.
www.universetoday.com/20620/lunar-year/
which does not evenly divide into the 365.25 days of the year.
Note: The Romans borrowed the calendar from the ancient Greeks to develop the idea of a 10-month calendar that left approximately 60 days unaccounted for.
Consequently, the earliest ancient Roman calendars had months that were either 29 or 30 days to account for this discrepancy.
The Romans started using the 10-month calendar in 738 B.C. that included Martius[March], Aprilis[April], Maius[May], Junius[June], Quintilis[July, quin- meaning "5"], Sextilis[August, sex- meaning "6"], September, October, November, and December.
To account for the remaining $pm60$ days, Januarius[January] was added to the beginning of the year and Februarius[February] to the end of the year during Numa's reign around 700 B.C with a leap year every 4 years. The calendar stayed in that order until 452 B.C. when a small council of Romans, called the Decemvirs, moved February to follow January.
However, people began adding a leap year every three years, so that caused a big problem. In fact, by the start of the reign of Julius Caesar, the previous calendar was off by a whole week!
Julius Caesar noticed this and thus modified the Roman calendar in 46 B.C. to make each month have either 30 or 31 days, with the exception of Februarius[February], which had 29 days, with the three year leap year fixed into a four year leap year, along with the nullification of a leap year when the year number is a multiple of 100. Quintilis[July] was later renamed Julius[July] in his honor. Likewise, Sextilis[August] later became Augustus[August] to honor Augustus Caesar, Julius' Aunt. Augustus[August] was also given an extra day (taken away from Februarius[February]), so that Augustus and Julius would have an equal number of days, representing their equal power.
This calendar was extremely accurate, but was still off as thousands of years later it was off by a day or so. Then a pope named Pope Gregory XIII modified the Julian calendar again in October 1582. This is the currently used Gregorian calendar. He made it so that
Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100, but these centurial years are leap years if they are exactly divisible by 400.
https://en.wikipedia.org/wiki/Gregorian_calendar
This calendar is the most accurate calendar there is, and won't be a single day off until the year of $pm 3500$ AD.
New contributor
$endgroup$
$begingroup$
There are some errors in this answer. Eg, before the adoption of the Julian calendar, leap years were decreed by proclamation the pontifex maximus, in such years an extra month was added to the calendar. In the Julian calendar, there is a leap day every 4 years (with no exception for century years), but in the initial 36 years of its adoption leap days were added every 3 years due to a misunderstanding (Romans used inclusive counting). See en.m.wikipedia.org/wiki/Julian_calendar#Leap_year_error
$endgroup$
– PM 2Ring
3 hours ago
$begingroup$
The Julian calendar drifts by approximately 3 days every 400 years. So after a few hundred years, not thousand years, the drift becomes noticeable (i.e. the seasons don't properly match the calendar), which is important for farming, and therefore human survival. The latest popular calendar, the Gregorian, drifts by about one day every 12000 years, if I remember correctly. Due to astronomical effects (the rotation of the Earth speeding up and slowing down, etc.) we can't be more precise than that. A calendar that's accurate today is extremely unlikely to be accurate in 12000 years' time.
$endgroup$
– CJ Dennis
2 hours ago
$begingroup$
@PM2Ring Ah I see. Are you able to edit that into my answer? I don't know enough to accurately type in what you said with an explanation. Perhaps may I quote you?
$endgroup$
– Max0815
10 mins ago
$begingroup$
@CJDennis I will fix this.
$endgroup$
– Max0815
10 mins ago
$begingroup$
@CJDennis its 3200 years for 1 day to be off. I checked in my notes from science class.
$endgroup$
– Max0815
2 mins ago
add a comment |
$begingroup$
You make a great point. The reason behind the discrepancy between the dates is due to a complicated history behind it.
The calendar is based on the calendar created by ancient Romans, which is based on one Moon cycle. One lunar cycle is
29.53 days.
www.universetoday.com/20620/lunar-year/
which does not evenly divide into the 365.25 days of the year.
Note: The Romans borrowed the calendar from the ancient Greeks to develop the idea of a 10-month calendar that left approximately 60 days unaccounted for.
Consequently, the earliest ancient Roman calendars had months that were either 29 or 30 days to account for this discrepancy.
The Romans started using the 10-month calendar in 738 B.C. that included Martius[March], Aprilis[April], Maius[May], Junius[June], Quintilis[July, quin- meaning "5"], Sextilis[August, sex- meaning "6"], September, October, November, and December.
To account for the remaining $pm60$ days, Januarius[January] was added to the beginning of the year and Februarius[February] to the end of the year during Numa's reign around 700 B.C with a leap year every 4 years. The calendar stayed in that order until 452 B.C. when a small council of Romans, called the Decemvirs, moved February to follow January.
However, people began adding a leap year every three years, so that caused a big problem. In fact, by the start of the reign of Julius Caesar, the previous calendar was off by a whole week!
Julius Caesar noticed this and thus modified the Roman calendar in 46 B.C. to make each month have either 30 or 31 days, with the exception of Februarius[February], which had 29 days, with the three year leap year fixed into a four year leap year, along with the nullification of a leap year when the year number is a multiple of 100. Quintilis[July] was later renamed Julius[July] in his honor. Likewise, Sextilis[August] later became Augustus[August] to honor Augustus Caesar, Julius' Aunt. Augustus[August] was also given an extra day (taken away from Februarius[February]), so that Augustus and Julius would have an equal number of days, representing their equal power.
This calendar was extremely accurate, but was still off as thousands of years later it was off by a day or so. Then a pope named Pope Gregory XIII modified the Julian calendar again in October 1582. This is the currently used Gregorian calendar. He made it so that
Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100, but these centurial years are leap years if they are exactly divisible by 400.
https://en.wikipedia.org/wiki/Gregorian_calendar
This calendar is the most accurate calendar there is, and won't be a single day off until the year of $pm 3500$ AD.
New contributor
$endgroup$
You make a great point. The reason behind the discrepancy between the dates is due to a complicated history behind it.
The calendar is based on the calendar created by ancient Romans, which is based on one Moon cycle. One lunar cycle is
29.53 days.
www.universetoday.com/20620/lunar-year/
which does not evenly divide into the 365.25 days of the year.
Note: The Romans borrowed the calendar from the ancient Greeks to develop the idea of a 10-month calendar that left approximately 60 days unaccounted for.
Consequently, the earliest ancient Roman calendars had months that were either 29 or 30 days to account for this discrepancy.
The Romans started using the 10-month calendar in 738 B.C. that included Martius[March], Aprilis[April], Maius[May], Junius[June], Quintilis[July, quin- meaning "5"], Sextilis[August, sex- meaning "6"], September, October, November, and December.
To account for the remaining $pm60$ days, Januarius[January] was added to the beginning of the year and Februarius[February] to the end of the year during Numa's reign around 700 B.C with a leap year every 4 years. The calendar stayed in that order until 452 B.C. when a small council of Romans, called the Decemvirs, moved February to follow January.
However, people began adding a leap year every three years, so that caused a big problem. In fact, by the start of the reign of Julius Caesar, the previous calendar was off by a whole week!
Julius Caesar noticed this and thus modified the Roman calendar in 46 B.C. to make each month have either 30 or 31 days, with the exception of Februarius[February], which had 29 days, with the three year leap year fixed into a four year leap year, along with the nullification of a leap year when the year number is a multiple of 100. Quintilis[July] was later renamed Julius[July] in his honor. Likewise, Sextilis[August] later became Augustus[August] to honor Augustus Caesar, Julius' Aunt. Augustus[August] was also given an extra day (taken away from Februarius[February]), so that Augustus and Julius would have an equal number of days, representing their equal power.
This calendar was extremely accurate, but was still off as thousands of years later it was off by a day or so. Then a pope named Pope Gregory XIII modified the Julian calendar again in October 1582. This is the currently used Gregorian calendar. He made it so that
Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100, but these centurial years are leap years if they are exactly divisible by 400.
https://en.wikipedia.org/wiki/Gregorian_calendar
This calendar is the most accurate calendar there is, and won't be a single day off until the year of $pm 3500$ AD.
New contributor
New contributor
answered 4 hours ago
Max0815Max0815
39111
39111
New contributor
New contributor
$begingroup$
There are some errors in this answer. Eg, before the adoption of the Julian calendar, leap years were decreed by proclamation the pontifex maximus, in such years an extra month was added to the calendar. In the Julian calendar, there is a leap day every 4 years (with no exception for century years), but in the initial 36 years of its adoption leap days were added every 3 years due to a misunderstanding (Romans used inclusive counting). See en.m.wikipedia.org/wiki/Julian_calendar#Leap_year_error
$endgroup$
– PM 2Ring
3 hours ago
$begingroup$
The Julian calendar drifts by approximately 3 days every 400 years. So after a few hundred years, not thousand years, the drift becomes noticeable (i.e. the seasons don't properly match the calendar), which is important for farming, and therefore human survival. The latest popular calendar, the Gregorian, drifts by about one day every 12000 years, if I remember correctly. Due to astronomical effects (the rotation of the Earth speeding up and slowing down, etc.) we can't be more precise than that. A calendar that's accurate today is extremely unlikely to be accurate in 12000 years' time.
$endgroup$
– CJ Dennis
2 hours ago
$begingroup$
@PM2Ring Ah I see. Are you able to edit that into my answer? I don't know enough to accurately type in what you said with an explanation. Perhaps may I quote you?
$endgroup$
– Max0815
10 mins ago
$begingroup$
@CJDennis I will fix this.
$endgroup$
– Max0815
10 mins ago
$begingroup$
@CJDennis its 3200 years for 1 day to be off. I checked in my notes from science class.
$endgroup$
– Max0815
2 mins ago
add a comment |
$begingroup$
There are some errors in this answer. Eg, before the adoption of the Julian calendar, leap years were decreed by proclamation the pontifex maximus, in such years an extra month was added to the calendar. In the Julian calendar, there is a leap day every 4 years (with no exception for century years), but in the initial 36 years of its adoption leap days were added every 3 years due to a misunderstanding (Romans used inclusive counting). See en.m.wikipedia.org/wiki/Julian_calendar#Leap_year_error
$endgroup$
– PM 2Ring
3 hours ago
$begingroup$
The Julian calendar drifts by approximately 3 days every 400 years. So after a few hundred years, not thousand years, the drift becomes noticeable (i.e. the seasons don't properly match the calendar), which is important for farming, and therefore human survival. The latest popular calendar, the Gregorian, drifts by about one day every 12000 years, if I remember correctly. Due to astronomical effects (the rotation of the Earth speeding up and slowing down, etc.) we can't be more precise than that. A calendar that's accurate today is extremely unlikely to be accurate in 12000 years' time.
$endgroup$
– CJ Dennis
2 hours ago
$begingroup$
@PM2Ring Ah I see. Are you able to edit that into my answer? I don't know enough to accurately type in what you said with an explanation. Perhaps may I quote you?
$endgroup$
– Max0815
10 mins ago
$begingroup$
@CJDennis I will fix this.
$endgroup$
– Max0815
10 mins ago
$begingroup$
@CJDennis its 3200 years for 1 day to be off. I checked in my notes from science class.
$endgroup$
– Max0815
2 mins ago
$begingroup$
There are some errors in this answer. Eg, before the adoption of the Julian calendar, leap years were decreed by proclamation the pontifex maximus, in such years an extra month was added to the calendar. In the Julian calendar, there is a leap day every 4 years (with no exception for century years), but in the initial 36 years of its adoption leap days were added every 3 years due to a misunderstanding (Romans used inclusive counting). See en.m.wikipedia.org/wiki/Julian_calendar#Leap_year_error
$endgroup$
– PM 2Ring
3 hours ago
$begingroup$
There are some errors in this answer. Eg, before the adoption of the Julian calendar, leap years were decreed by proclamation the pontifex maximus, in such years an extra month was added to the calendar. In the Julian calendar, there is a leap day every 4 years (with no exception for century years), but in the initial 36 years of its adoption leap days were added every 3 years due to a misunderstanding (Romans used inclusive counting). See en.m.wikipedia.org/wiki/Julian_calendar#Leap_year_error
$endgroup$
– PM 2Ring
3 hours ago
$begingroup$
The Julian calendar drifts by approximately 3 days every 400 years. So after a few hundred years, not thousand years, the drift becomes noticeable (i.e. the seasons don't properly match the calendar), which is important for farming, and therefore human survival. The latest popular calendar, the Gregorian, drifts by about one day every 12000 years, if I remember correctly. Due to astronomical effects (the rotation of the Earth speeding up and slowing down, etc.) we can't be more precise than that. A calendar that's accurate today is extremely unlikely to be accurate in 12000 years' time.
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– CJ Dennis
2 hours ago
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The Julian calendar drifts by approximately 3 days every 400 years. So after a few hundred years, not thousand years, the drift becomes noticeable (i.e. the seasons don't properly match the calendar), which is important for farming, and therefore human survival. The latest popular calendar, the Gregorian, drifts by about one day every 12000 years, if I remember correctly. Due to astronomical effects (the rotation of the Earth speeding up and slowing down, etc.) we can't be more precise than that. A calendar that's accurate today is extremely unlikely to be accurate in 12000 years' time.
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– CJ Dennis
2 hours ago
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@PM2Ring Ah I see. Are you able to edit that into my answer? I don't know enough to accurately type in what you said with an explanation. Perhaps may I quote you?
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– Max0815
10 mins ago
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@PM2Ring Ah I see. Are you able to edit that into my answer? I don't know enough to accurately type in what you said with an explanation. Perhaps may I quote you?
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– Max0815
10 mins ago
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@CJDennis I will fix this.
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– Max0815
10 mins ago
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@CJDennis I will fix this.
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– Max0815
10 mins ago
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@CJDennis its 3200 years for 1 day to be off. I checked in my notes from science class.
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– Max0815
2 mins ago
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@CJDennis its 3200 years for 1 day to be off. I checked in my notes from science class.
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– Max0815
2 mins ago
add a comment |
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I've added an extra sentence to keep your question on-topic in Astronomy and not just about the history of calendars and how the month is defined for modern Gregorian calendars.
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– uhoh
5 hours ago
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only slightly related, calendar history/trivia in VSauce's How Earth Moves
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– uhoh
4 hours ago