절월·일진 기준
Yellow/black path
A traditional division of twelve spirits into yellow and black paths, determined from the solar-term month and day branches.
How did it begin?
青龍, 明堂, 金匱, 天德, 玉堂 and 司命 form the yellow path; 天刑, 朱雀, 白虎, 天牢, 玄武 and 勾陳 form the black path. This date-selection convention differs from the astronomical ecliptic and does not predict fortune or impose a compulsory prohibition on activities.
Calculation rules
青龍 starts on 子 days for 寅/申 months, 寅 for 卯/酉, 辰 for 辰/戌, 午 for 巳/亥, 申 for 子/午, and 戌 for 丑/未. Following day branches receive 青龍, 明堂, 天刑, 朱雀, 金匱, 天德, 白虎, 玉堂, 天牢, 玄武, 司命 and 勾陳 in order. The month follows solar terms rather than lunar months. For 2020–2050, it changes on the Korean Standard Time calendar date of each jie boundary, applying to the whole date rather than the exact instant. Missing required solar-term data leaves the value unavailable. WhatDay365 uses the device’s local date, changing the day at midnight (00:00). Lunar and day-pillar conversion supports Gregorian dates 1000-02-13 through 2050-12-31; dates outside this range are not estimated.
Source · 欽定協紀辨方書 · 卷七 · 黃道黑道 ↗ (new window)