The Great One on Xun, south east
Xun runs from 127.5 to 142.5 degrees, centred on 135. It is one of the four corner trigrams, a wood mountain, with Chen on its left and Si on its right. Its opposite is Qian at 315, a common sitting and facing pair.
The star ring places Taiyi here. Among the 24 the school counts four as noble, and Taiyi is one. Its imagery is scholarship and clean honour, standing earned by study rather than force, the quietest of the four noble names. That is all the name says; it does not hand out degrees or titles.
A noble star on an elegant mountain
This is one of the four bearings where the school allows itself to say a site carries the best of the sky. Xun is an elegant mountain, so a clean upright peak on it counts as a xiu peak by the older landform rule, and the star above it is noble; the two readings agree.
The order does not change: dragon first, then guarding hills and water mouth, then the plate sighted on the Xun peak. If it is a true xiu peak, Taiyi confirms the best of what the hills have shown. If Xun holds a scarred, leaning or quarried hill, the noble star has nothing to confirm. Nobility on the ring is only as good as the hill it answers.
What this means on the ground
Find Xun on the 24 mountain ring and read Taiyi in the same sector of the star ring. At a grave, stand behind the stone along its face, level the plate, three readings. Sight the south east peaks across the centre; one between 127.5 and 142.5 is a Xun peak, and its outline should show a clean top and whole sides. Water first seen on Xun is noted the same way.
For a house, stand inside the front door facing out. A tidy tower, a pointed roof or a neat hill on 135 degrees is the Xun sand; the school wants it upright and finished, not the tallest. A reading near 128 or 142 is on the line with Chen or Si; take it again from a step aside.
Common mistakes
Chasing the bearing without the peak. A noble star on the ring with an empty or broken skyline on Xun is nothing; Taiyi needs a real xiu peak to answer. Reading nobility as a result: people hear Great One and expect scholars in the family. The star confirms a clean form, no more.
Letting the star excuse the dragon: a dead, flat range with a fine Xun peak beside it is still dead. Taking the star from an app or a general compass; the four noble pairings belong to the school's own ring. Sighting from a satellite image, which gives no place to stand.
Questions people ask
What is the Taiyi star in feng shui?
Taiyi, the Great One, is the Tianxing star paired with Xun, the mountain at 135 degrees south east, and one of the school's four noble stars. Its name stands for learning, writing and clean honour.
Is Xun a good direction for a house?
Xun is an elegant mountain and the seat of a noble star, which counts for a clean hill or building on that bearing outside your door. It is a test for the sand, not a rule for the facing.
Does a noble star fix a bad plot?
No. The school reads the star after the landform, never instead of it. A poor dragon, open guarding sides or a loose water mouth are not repaired by Taiyi on the ring; the star confirms a good form and does not create one.
To have a Xun peak sighted and the noble star read at your plot, book a site visit with Master Zhang or join the field course in Ganzhou.