Chandra or Soma was th son of the sage Atri. Atri was a very powerful sage. He was always busy meditating. For three thousand years he performed tapasya, with his arms raised up into the air. He stood there, immobile like a tree-trunk. As a result of this wonderful tapasya, energy issued out of his body. The goddesses who preside over the ten directions assimilated this energy and produced Chandra. It was in this sense that Chandra was the sage Atri‘s son.
Brahma gave Chandra a divine chariot to ride on. This chariot was drawn by one thousand white horses. Chandra ascended the chariot and rode around the earth twenty-one times. While he was doing so, some energy from his body fell down on the earth. This was the origin of the herbs. Brahma appointed Chandra ruler over herbs, seeds, brahmanas and the water.
Chandra performed a royal sacrifice (rajasuya yajna). The success of this ceremony however served to turn Chandra‘s head. The preceptor of the gods was Brihaspati and Brihaspati‘s wife was named Tara. Although Chandra had already been married to twenty-seven of Daksha‘s daughters, he abducted Tara. The gods and the sages requested Chandra to return Tara, but he would not listen. A terrible fight then raged between the gods and the demons, the gods fighting on Brihaspati‘s side and the demons on Chandra‘s. After Tara‘s name, this samgrama (war). Finally, Brahma intervened and sorted the matter out. Chandra returned Tara to Brihaspati.
But Chandra and Tara had a son named Budha. You will remember Ila, Vaivasvata Manu‘s daughter. Budha married Ila and their son was called Pururava. Pururava was the originator of the lunar line.