The Asgardian calendar is available at :
This is an excellent piece of work, the site and it's interactive presentation of the Calendar is excellent. Given this success, the question must be asked. Is this the final version or can we ...
The Asgardian calendar is available at :
This is an excellent piece of work, the site and it's interactive presentation of the Calendar is excellent. Given this success, the question must be asked. Is this the final version or can we build on these solid foundations and further improve the calendar? To make it universal and able to convert between all calendars that Asgardia may need in the future. That would seem to be to be the logical way forward. What must be done to extend the calendar to achieve these goals?
A note on modelling
A calendar is a model of reality, normally created for coordination and predictive purposes. Calendars can be used to predict when is the best time to plant and harvest crops, when animals migrate and so when to hunt them and how much daylight there will be at a certain time of the year. That is assuming a solar based calendar, moon based calendars can be used to predict tides and other animal behaviour. Calendars can also be used to coordinate activities. There can be multiple calendars, taking different cycles into account, so conversion between calendars is required.
Calendars are about astronomical cycles, such as the time a planet takes to orbit it's star or a natural satellite takes to orbit it's planet. Planets spin, so the number of spins (days) in a cycle is normally what we are interested in, in particular the timing and duration of day and night. The fundamental problem is these phenomena are natural and unfortunately no orbit of any body around any other will be an exact number of days. Hence if we assume integer numbers of days per year we need to add (or subtract) an extra one every so often to keep the model reasonably close to the astronomical reality. Historically we have used simple rules to do this, but this is not perfect and requires revision periodically.
So, a parameterised universal leap year calculation that minimises the drift of days in a year, makes sense. The only parameter required is the length of the year in local days as a real number. The start of Era may or may be a leap year itself.
In summary, a calendar is the synchronisation of 2 cycles by inserting 'leap' periods. On other planets a leap second would be required too every so often, given the second is a fraction of an Earth day, and it is sensible to keep the SI units.
Structure of dates
A calendar minimally requires 2 numbers to make it work, the number of planetary rotations in the orbit (the Earth around the Sun for example). In essence, we are trying to maximise the usefulness and predictive capability of the model without making it too complicated (and keeping the number reasonably small and tractable). So we could simply say a date is Year.Day (with 365.24219878 days in a year approximately on Earth). To turn this into 2 integers we require an day to be added at the end of the year periodically, called a leap year. If it were not added at the end of the year the day numbers would jump about between normal and leap years, which is highly undesirable.
Now, traditionally on earth we have tried to accommodate lunar cycles into this scheme too, calling them months. This does not 'fit' very well mathematically. However, as humans we find the additional concepts of months and weeks convenient for our activities. To justify this we think of months as approximating lunar cycles (but the drift makes this rather impractical) or with reference to the appearance of the 'fixed' stars, on which our brains project patterns, a sequence of constellations as they are called. Historically (in the West), this has resulted in a calendar with 3 cycles, years, months, and days (or 4 cycles with weeks). We are so familiar with this convention, it seems 'natural', it is actually just locally convenient and historical.
With the introduced concepts of months and weeks, and thousands of year