Of these 28 constellations (nakṣatra), those of Uttaraphālguni, Uttarāṣāḍha and Uttarabhādrapada together with the constellation of Rohiṇī are known as ( Dhruva ) stable asterisms. Coronation of kings, expiatory ceremonies, planting of trees, the building of towns, acts of public utility, the sowing of seeds and acts of permanent effects shall he commenced when the Moon passes through the stable asterisms.