Metamorphoses Book 2: Phaethon
Epaphus was friends with Phaethon, son of Clymene. Clymene told Phaethon that his father was the sun god, Phoebus or Apollo, but the boy wanted proof. Phaethon journeyed to the palace of the sun in Ethiopia to ask the sun god for proof that he was the boy's father. Phoebus vowed on the river Styx that as Phaethon's father, he would grant him his heart's desire. Unfortunately, Phaethon's wish was to drive his father's chariot across the sky. Powerful, fiery horses pulled Phoebus's chariot and their journey across the sky from east to west is what provided sunlight to the earth each day. Phoebus tried to dissuade his son because of the grave danger of the journey, but Phaethon wouldn't give up his wish, and so Phoebus had to agree because he'd made a binding vow to his son.
Phaethon took the horses up into the sky and the chariot raced out of control because the boy couldn't control the horses. Weaving throughout the constellations and up to the apex of the sun's journey, the horses ran wild through the sky leaving a trail of fire behind them that dried the rivers of the earth and evaporated the oceans. The heat turned the skin of the Aethiops black and created the vast Sahara desert. Even the heavens were in flames. The earth cracked and trembled in pain and Mother Earth cried out to Jove for help. Jove could not make it rain because all the water had disappeared, so he hurled a lightning bolt to knock Phaethon and the chariot from the sky. The bolt extinguished the great fire and killed Phaethon.
Phaethon's body was buried in a tomb in that foreign land, and his mother and three sisters set out to find the tomb. When they reached his burial place, the women mourned there so long that the girls turned into poplar trees and their tears formed amber.
Cycnus, Phaethon's kinsman and lover, left his home and came to Phaethon's tomb to mourn him among the poplar grove of Phaethon's sisters. There the man grieved until he was transformed into "a strange new bird, a swan, that fears / To trust the sky or Jove, remembering / The unfairness of that fiery bolt he hurled." Book 2 -- Phaethon, line 376-8
Phoebus was so distraught over his son's death that he refused to drive the chariot of the sun anymore. He was angry that Jove had killed Phaethon. For a day the earth went without the light of the sun. Finally Jove forced Phoebus to drive the chariot again.