Case 02 of 26
Solar-term boundaries
After Lichun: the Bazi year changes
The paired case moves beyond Lichun and changes both year and month pillars.
Boundary question
What changes after the Lichun boundary has passed?
The chart moves to the Bing-Wu (丙午) year and Geng-Yin (庚寅) month, showing that the boundary is solar-term based.
Synthetic input
Recorded facts
- Date
- 2026-02-05
- Recorded time
- 12:00
- Location
- 120°E reference meridian
- Time zone
- Asia/Shanghai
- Longitude
- 120.0000°
- Gender input
- Male
Pinned expected facts
Verified output
Year
丙午
Month
庚寅
Day
庚戌
Hour
壬午
- Day Master
- 庚
- True solar time
- 2026-02-05 11:46
- Total correction
- -13.74 minutes
- Historical offset
- UTC+08:00 · DST 0 min
- Luck direction
- 顺排
- Reference Jie
- 惊蛰 · 2026-03-05 21:59:00
- Luck start
- 2035-07-26 13:16:15
Conventions and limits
What this case does — and does not — prove
It verifies
Deterministic reproduction of this input under the named engine version and conventions. A pinned-field mismatch stops the production build.
It does not claim
Universal agreement across Bazi schools, interpretation of a real person, or certainty where the historical record is incomplete.
tyme4ts 1.5.2 · cantian-tymext 0.0.27 · sect 2 day boundary · BaziCalculator.ai NOAA/IANA true-solar adapter
calculation-benchmarks-v1 · reviewed 2026-09-05