Helios was a sun god in ancient Greek mythology. According to Hesiod's "Theology" [1], he was the son of the Titan god Hyperion and Thea, the brother of the moon goddess Selene and the dawn goddess Aeos. It is said that he rode a sun chariot pulled by four fiery horses in the sky every day, from east to west, rising in the morning and setting in the evening, allowing light to shine throughout the world. In later mythology, he and Apollo were gradually mixed together. In Rome, he was called Sol.

Helios λιος， In Greek mythology, the personification of the sun is commonly used by Homer in the Iliad ερίων” To modify or directly refer to him, sometimes also using“ Τιτάν” Refers to him. In the Odyssey [3], he is referred to as' Ὑπ ' εριωνίδης (Son of Hyperion) "; Hesiod's" Theology "and" Homer's Prayer to Helios "refer to him as the son of Hyperion and Thea (Euriphaesa), the brother of the moon goddess Selene and the dawn goddess Aeos. Roman Ovid in the" Metamorphosis "[5] referred to him as" Lumina Titan " . Mythology portrays Helios as a tall, muscular, handsome, and unnecessary handsome man. He was dressed in a purple robe and wore a golden crown of the sun that emitted countless beams of light. Every day, when the goddess of dawn, Aeos, opened the heavenly gate with her rose colored fingers, Helios rode a sun chariot pulled by four flaming horses and began to travel westward until dusk fell on the other shore of Ochianus. These four Flame Horses are: Pyros, Helios, Eton, and Falcon. In later mythology, Helios gradually became confused with Apollo. Nevertheless, they are often regarded as two different gods (Helios is the god of Titan, and Apollo is the god of Olympus, but both belong to the Olympus family). Helios is equivalent to the Sol in Roman mythology, especially the "Sol worship".

Ἥ λιος The original meaning of 'sun' is derived from the primitive Indo European * s ó h ₂ wl ̥ ， This is homologous with words such as sol in Latin, सूर्य in Sanskrit, swegl in Old English, sunna in Germanic, and haul in Welsh [6].

Phaethon
Quoting the long mythological satirical poem "Metamorphosis" by Roman Ovid [5]
Phaeton, in order to prove that he was the son of Helios, requested from his father to receive Helios' oath to give him anything he wanted. He then demanded to drive his father's sun chariot for a day, from the sunrise in the eastern sky to the sunset in the west. The sun god tried every means to persuade him that he could not control the sun chariot, which would bring harm to himself and humanity. Fa Etong did not listen and drove away on the sun chariot. Due to the burning horse feeling that the carriage was very light and the load was usually light, it rose too high and the earth suddenly became cold; At this point, Faetong was no longer able to control the sun chariot, and it rapidly descended, causing the grass and trees on the ground to be charred, many mountains to burn up, the green springs and lakes to run out, and the rivers to be burned dry. Libya has become a desert, and the skin of Ethiopian residents has also been burned black and red. Gaia constantly complained and complained to Zeus. Finally, Zeus had to personally strike Phaethon to death with a thunderbolt. The body fell into the Eridanos River. It is said that Phaeton was buried in the sea because Helios had made a solemn oath to the oath river Styx in the Styx. If Phaeton made unreasonable demands, he would surely die without a burial place, and the oath made to Styx cannot be retracted. In the end, Phaeton should swear to die without a burial place, which was the deity of the Eridanos River, Naiades, who could not bear his soul to return. Therefore, he buried his bones with seawater, And when her mother and sister learned about it, they wept at the sea where his bones were buried, tears turned into amber, and their bodies turned into poplar trees.
sunflower
Quoting the long mythological satirical poem "Metamorphosis" by Roman Ovid [5]
Clutius is a goddess of the sea. She was once the lover of Helios, but later Helios fell in love with the Persian princess Lyukotoe. Cynthius, who was burning with jealousy, reported the relationship between Lycotoe and Helios to the Persian king Orkamos. Orkamos ordered the burial of his unfaithful daughter alive. After Helios learned of this matter, he completely cut off his dealings with Clutius. The infatuated Clythius didn't eat or drink, staring at Helios driving his solar car up and down, gradually becoming haggard and eventually turning into a sunflower.

The theory that Apollo was the sun god was derived from the addition of some ancient Greek poets and playwrights.
Since the fifth century BC, the sun god Helios has been severely confused with the art god Apollo. Therefore, Apollo is believed to be Helios, the sun god. However, due to Helios not completely mixing with Apollo in the end, Therefore, some later non Greek writers wrote about things like "After the Battle of Titanomachy, the god Zeus rewarded the gods, and the god of light Apollosus wanted to take charge of the sun. Zeus forgot about Helios, who was on duty, and agreed to Apollo's request. There is also a theory that because Phaeton, the son of the sun god Helios, caused disasters by driving a solar chariot, Zeus entrusted Apollo with the responsibility of controlling the solar chariot These 'myths'.
Of course, this is what later writers claim, and it is not written by the ancient Greeks and cannot be considered Greek mythology. (Helios has been a sun god since birth and will always be)
In late ancient Greece, people often worshipped Apollo as the sun god: in addition, Helios' earlier nickname, Phoebus (meaning to shine), also became a nickname for Apollo, which was later used by Latin poets on top of the Roman sun god Sol. At this point, the confusion between Apollo and Helios has become increasingly intense to the point where it can be seen everywhere. (Regarding the name Helios, its original meaning includes "radiant," "radiant," and "bright." Therefore, it can be confirmed that in ancient Greek mythology, the sun god was indeed Helios.)

commentary
The incomplete merger of Apollo and Helios had already been formed as early as the ancient Greek period. In Homer's writing, Helios is the sun god. In early Greek literature such as the Homeric Epic, there was no mention of Apollo driving the solar car. The eighth volume of the Odyssey, from lines 265 to 270 and from lines 300 to 303, explicitly states twice that the sun god is Helios.
The era of Homer's life was around the 8th century BC, and by the 5th century BC, Greek mythology underwent a significant transformation, during which the incomplete merger of Apollo and Helios was formed. The earliest record of the incomplete merger between Apollo and Helios should be from Euripides' tragedy Phaeton. In the concluding section, Clymene laments that Helios destroyed her son. Here, she calls Helios Apollo, meaning the destroyer, and there is indeed such a presence in Apollo's attributes. In the Iliad, Apollo immediately sent a plague to the Greek army after hearing the prayer of the high priest, as the daughter of Chryseus was kidnapped, which is a good example.
Phoebus was originally the god of light in ancient Greece, but over time, he eventually completely merged with Apollo. In the 24th volume of the Iliad, Apollo was already known as Phobos Apollo. As a result, the identity of Apollo as the "God of Light" gradually took shape.
It is certain that the complete merger between Apollo and Phobos occurred much earlier and much earlier than the incomplete merger between Apollo and Helios