As of May 31, 2023, we have updated our Code of Conduct.

Questions tagged [calendar]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
1 vote
1 answer
75 views

Is there another calendar with the equivalent of gregorians weeks?

In the gregorian calendar, we split the time in years, months, weeks and days. A week is the total of seven days. I was looking at the persan calendar, being one of the most precise known calendar. ...
Itération 122442's user avatar
2 votes
1 answer
147 views

Did the 1800 Gregorian Lunar Correction Motivate Gauss' Computus Algorithm?

When the Gregorian calendar was implemented in 1582, one of its adjustments was the lunar correction---to increase the epact by 1 eight times within a span of 2500 years; specifically, seven times ...
mlchristians's user avatar
4 votes
0 answers
116 views

Was the oldest Chinese calendar a solar calendar?

Recently I read the English Wikipedia article about the Chinese calendar. Surprisingly, the article stated that the oldest Chinese calendar was a solar calendar (or solar calendars). The ...
pdh0710's user avatar
  • 181
5 votes
1 answer
101 views

Spirals as calendrical representations

A recent work proposed that the double spiral motif found at Newgrange (ca. 3200 BC) is a calendrical representation. Looking south the northern peoples observed that the arc traced by the sun widens ...
sand1's user avatar
  • 2,377
0 votes
2 answers
116 views

Were people in the ancient or medieval times aware of how exactly a solar year is equal to a lunar year?

Was it common knowledge around 600 AD or perhaps 30 BCE that 200 solar years for example were equal to 209 lunar years? In which period of history precisely can we say that such a thing was confirmed?
Malux's user avatar
  • 1
1 vote
2 answers
971 views

Why was 0000 chosen to be the start of the calendar?

What's the significance of date 0000? Why was this day chosen to be the start of the calendar? What comes before 0000? I know they say 1BC. But then shouldn't current time be called AD? Don't know ...
GypsyCosmonaut's user avatar
2 votes
2 answers
399 views

Length of the year in Aztec/Maya calendar

In an old book of Prescott (died in 1859), The conquest of Mexico, the author described Aztec calendar with a year of 365 days. To compensate for the difference, every 52 years an additional 12.5 days ...
Alexandre Eremenko's user avatar
10 votes
3 answers
2k views

Why should February have 28 days?

According to the Gregorian calendar the second month i.e. February have 28 days and in a leap year 29 days. I am not sure what calculations(science) it takes to decide the total number of days in ...
Amit Tyagi's user avatar
  • 1,468
26 votes
5 answers
8k views

Is there an astronomical reason behind the order for the names of days of the week?

The seven days of the week seems to be commonly named after celestial bodies. What I find curious is that all seven days apparently share the same names in both West and East. Sunday is, of course, ...
Semaphore's user avatar
  • 595