Daksha had 27 daughters by his wife Prasuti, all of whom were married to Chandra. He cursed his son-in-law when he found that despite his promise of equal treatment, he had continued to favour Rohini over all the others. According to this curse, Chandra goes through periodic waxing and waning of his lustre, of which he was inordinately proud. This is the popular explanation for the phases of the moon.
Legends of Daksha
The full account of the great sacrifice of Daksha can be found in Vayu Purana. Sati, one of the daughters of Daksha was married to Lord Shiva against his wishes. Daksha attempted to insult Shiva by performing a sacrifice and omitting to invite Shiva. His daughter wanted very much to attend the sacrifice. Ignoring the advice of her husband, she went uninvited to the sacrifice, where she had to endure many insults. At last, when Daksha started insulting her husband, she could not bear it any longer and immolated herself in the sacrificial fire.
On hearing about the death of Sati, Lord Shiva was infuriated. The angered Shiva tore off a lock of his hair and cast it with violence to the ground. It took the form of Vira Bhadra, who had a thousand hands. Then, Lord Shiva sent him to destroy the sacrifice of Daksha. According to some legends, it is believed that Vira Bhadra cut off Daksha's head.
Again, as per the Vishnu Purana, Vira Bhadra; the killer of Daksha was created from Shiva's mouth. It is said that the Gods displayed at the conduct of Vira Bhadra, who destroyed the sacrifice of Daksha. Hence, all the Gods went to the Lord Brahma and complained against him. Thereafter, Lord Brahma went to Lord Shiva and requested him on behalf of Daksha to negotiate the matter. Then Lord Shiva went to the scene of disorder and revived Daksha. But, as his head was not found, it was replaced with that of a ram.