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In my novel, I have created an intergalactic empire that predates humanity by millions of years. The only system I am having a difficult time creating, for this empire, is a Calendar system that operates off of cycles of the universe; not of a local planet. However, finding information about the cycles of the universe is like looking for a needle in a haystack.
Does anyone have any information about the cycles of the universe that might be helpful for creating a kind of intergalactic calendar?
In my system there should be an intergalactic date, a planet symbol, and then base a calendar off that planet so that there’s five sets of digits in the dating system.
- galactic year - GY (?)
- Planet - P (which planet)
- Local Year - LY (planetary year)
- Local Cycle - LC (planetary month)
- Local Sub-Cycle - LSC (planetary day)
Time is based on a UTC type of synchronization using what amounts to an atomic clock when in space which is synchronized to a local planetary subdivision of a day using a base of that planet's cycles, such as a base 10, base 12, base 24, base 30, base 100, etc. - a numeral system for pre-colonized worlds such as earth.
- day (light / dark cycle)
- hour (large time grouping)
- minute (medium time grouping)
- second (small time grouping)
- millisecond (tiny time grouping)
The empire is highly advanced and logical so I want to ensure the logic applies also to their calendar system.
Any suggestions or recommendations are greatly appreciated.
Edit: This question is about observable phenomena in the universe that could be measured and used for time keeping, it's not a question of how to make a calendar. 200 million years per revolution of the milky way is on the right path. How about cycles of the universe as a whole?