What is the Tian Yue (Moon) star?

First, to be clear: this Tian Yue (Heavenly Moon) is not the Tian Yue (Heavenly Halberd) of the Six Auspicious Stars. Tian Yue (Heavenly Halberd) is about benefactors and opportunities; Tian Yue (Heavenly Moon) is a very light minor star placed by birth month. The two names only sound alike, and in pinyin they are spelled the same. Wang Tingzhi of the Zhongzhou school says outright that "Tian Yue is an illness star," linking it to the state of the body. Xingge doesn't read health from this star, and treats it only as a reminder to look after your own pace. To find out which palace Tian Yue (Heavenly Moon) falls in, draw your chart.

What kind of star is Tian Yue (Heavenly Moon)

Tian Yue (Heavenly Moon) is neither a helpful star nor a challenging one; it is a neutral small star that leans toward reminders. Wang Tingzhi also says that even when the Health Palace has Tian Yue (Heavenly Moon), it doesn't necessarily mean illness: it only counts when read with the whole group of stars, and it leans toward the drawn-out, slow kind. Later astrology books take up the bodily side; Xingge reads it in terms of routine and pace instead: the palace it sits in is where you're more likely to push yourself too hard and need to leave a little more room.

How Tian Yue (Heavenly Moon) is placed: by birth month

Tian Yue (Heavenly Moon) goes only by your lunar birth month. The common verse is "First the dog, second the snake, third at the dragon; fourth the tiger, fifth the goat, sixth the rabbit's palace; seventh the pig, eighth the goat, ninth at the tiger; tenth the horse, winter the dog, and the last month at Yin." In Earthly Branches:

• 1st month: Xu
• 2nd month: Si
• 3rd month: Chen
• 4th month: Yin
• 5th month: Wei
• 6th month: Mao
• 7th month: Hai
• 8th month: Wei
• 9th month: Yin
• 10th month: Wu
• 11th month: Xu
• 12th month: Yin

In the verse, "winter" means the 11th month and "the last month" means the 12th. Tian Yue (Heavenly Moon) isn't in the Zi Wei Dou Shu Quan Shu (The Complete Book of Zi Wei Dou Shu); later astrology books added it, and Xingge places it on the chart by the common method.

Tian Yue (Heavenly Moon) in key palaces

This star is very light, and Xingge's chart readings don't write a separate line for it. Below are directions worth noticing when you read the chart:

• Life Palace: you tend to throw yourself into things and forget to stop. Scheduling your rest matters as much as scheduling your work.
• Health Palace: on Xingge, this palace only talks about stress and daily rhythm. With Tian Yue (Heavenly Moon) here, the reminder is to stop when you're tired, and not to push through to the very last moment.
• Travel Palace: away from home or on business trips, your routine easily falls apart. A looser itinerary works better than catching up on sleep when you get back.
• Career Palace: when busy, you keep adding more. It helps to set yourself a finishing time each day and to take your time off.
• Fortune Palace: your mood and your physical state are closely linked; when you sleep badly, your mood drops too. Look after your routine first, and your mind steadies too.

Reading Tian Yue (Heavenly Moon) with main stars and other stars

• Main stars: when Tian Yue (Heavenly Moon) meets hard-charging stars like Qi Sha or Po Jun, the reminder is clearer: after a sprint, there needs to be a time to ease off. With slower-paced or caretaking stars like Tian Tong or Tian Liang, it's often someone who looks after others first and forgets themselves.
• Helpful stars: when it shares a palace with small stars that carry a sense of turning things around, like Tian De, Yue De or Jie Shen, the reminder is lighter.
• Annual Luck: Tian Yue (Heavenly Moon) goes by birth month and doesn't move with the Annual Luck. When the annual Life Palace reaches its cell, you can treat that year as a good one for adjusting your routine and not packing your schedule.

How the schools differ

The month table is much the same across schools. The most common difference is the leap month: whether a leap-month birth counts as that month or the next, and if the month changes, Tian Yue (Heavenly Moon) changes cell. Xingge follows most modern charting: days 1 to 15 of a leap month count as that month, and days 16 onward as the next month.