Sui-Gen's astronomical data was pre-computed using
Skyfield against NASA JPL's DE440 and DE441 planetary
ephemerides, the same numerical integration models used for interplanetary spacecraft
navigation. New moon moments and solar term crossings were resolved to sub-second precision
and converted to Beijing Time (UTC+8).
Data
Coverage
DE440 (covering 1550-2648 CE) was used where available, as
it includes modelling of the Moon's liquid core and mantle coupling for higher accuracy.
DE441 (covering 619-17190 CE) was used for the historical and far-future ranges
outside DE440's coverage. Accuracy is sub-second within the DE440 range. For dates
outside this range, accuracy degrades gradually due to uncertainty in ΔT (the difference
between Terrestrial Time and Universal Time).
Cycle
Stability
Zodiac, element, and Ganzhi cycle fields are computed
separately via pure 12- and 60-year cycle arithmetic and are 100% reliable for any
year.
Precomputed
Datasets
The following JSON datasets, spanning 619 to 17190 CE, are
available for direct download. All timestamps are given in both Terrestrial Time (TT) and
approximate UTC.