Zhen, the Chariot, is the twenty-eighth and last of the xiu and the final mansion of the southern palace, the Vermilion Bird. Its name means a chariot or carriage, identified with stars in Corvus. In the later astrological tradition its animal totem is the Earthworm. As the last of the twenty-eight lunar mansions it closes the circle of the sky; after the Chariot the count returns to the Horn of the Azure Dragon. These are the conventions of the Chinese astronomical and calendrical tradition, in which the twenty-eight xiu, grouped into the four palaces of the Azure Dragon, Black Tortoise, White Tiger, and Vermilion Bird, divide the heavens along the celestial equator and underlie the almanac's assignment of fortune to the mansion the Moon occupies.
Zhen closing the cycle at the Chariot completes a southern palace whose seven mansions, Well, Ghost, Willow, Star, Extended Net, Wings and Chariot, trace the Vermilion Bird from wing through neck, crop, tail feathers and back to a concluding image entirely unlike the ordinary body plan used for the other three palaces, the finishing image here a vehicle rather than a further body part, which some commentators read as marking the completed cycle's return to worldly, wheeled motion just before the count restarts at Jiao's horn.