Phobos

Phobos was the son of Ares, and Aphrodite in Greek mythology. He was associated with fear, dread, and panic, as his name directly translates. He is often depicted as a man with the head of a lion, holding a spear, commonly called "Phobos' Spear of Panic." He had a twin brother, Deimos. His Roman counterpart is Timor, or Timorus.

The suffix "-phobia", representing an irrational fear of something, derives from Phobos and, ultimately, the Greek word "φόβος", meaning "fear".

His name was given to a moon of the planet Mars.

☀Phobos (Ancient Greek: Φόβος,  pronounced  [pʰóbos], meaning "fear") is the personification of fear in Greek mythology. He is the offspring of Aphrodite and Ares. He was known for accompanying Ares into battle along with the ancient war goddess Enyo, the goddess of discord Eris (both sisters of Ares), and Phobos' twin brother Deimos (terror).

In Classical Greek mythology, Phobos is more of a personification of the fear brought by war and does not appear as a character in any myths. Timor or Timorus is his Roman equivalent. In Roman mythology, he has also been referred to as Pavor.

Genealogy
Phobos is the son of Aphrodite and Ares. This may be seen in Hesiod's Theogony, "Also Kytherea Aphrodite bare to Ares the shield piercer Phobos…" (Atsma). Ares was accompanied in battle by his sister Eris, Phobos, and Deimos. Phobos's genealogy is shown:

Worship
Those who worshipped Phobos often made bloody sacrifices in his name. In Seven Against Thebes by Aeschylus, the seven warriors slaughter a bull over a black shield and then "touching the bull’s gore with their hands they swore an oath by… Phobos who delights in blood…"(Atsma). Ares's son, Kyknos, "beheaded strangers who came along in order to build a temple to Phobos (fear) from the skulls." (Atsma).

Warriors and heroes who worshipped Phobos, such as Heracles and Agamemnon, carried shields with depictions of Phobos on them.

Because Aphrodite was their mother, Phobos and Deimos were gods of the fear of loss.

Depictions
Hesiod depicts Phobos on the shield of Heracles as "…staring backwards with eyes that glowed with fire. His mouth was full of teeth in a white row, fearful and daunting…" (Atsma) and again later during a war scene as being "…eager to plunge amidst the fighting men," (Atsma).

Deimos and Phobos were represented as young boys. Phobos often is depicted as having a lion's or lion-like head. This may be seen in Description of Greece by Pausanias, "On the shield of Agamemnon is Phobos (Fear), who[se] head is a lion’s…" (Atsma).

Historical reference
According to Plutarch, Alexander the Great offered sacrifices to Phobos on the eve of the Battle of Gaugamela (in all probability asking for Darius to be filled with fear). This was believed by Mary Renault to be part of Alexander's psychological warfare campaign against Darius III. Darius fled from the field of Gaugamela, making Alexander's praying to Phobos seem successful as a tactic.

Phobos was depicted on the chest of Cypselus on the shield of Agamemnon.[1]

Astronomy
American astronomer Asaph Hall named a satellite of the planet Mars, "Phobos", which he discovered along with the second Mars satellite, "Deimos", in 1877. Phobos is the larger of the two satellites.[2]

Psychology
The word "phobia" derives from phobos, (Φόβος), meaning fear.

Deimos and Phobos in Sparta
The two brothers Deimos and Phobos were particularly worshipped in the city state of Sparta as they were the sons of Ares, the god of war. Phobos in Greek literally means fear (Ancient Greek: Φόβος). Spartan soldiers would idolize Phobos, because he symbolized discipline, and consistency of the armed forces. Because Phobos and Deimos were key mythological characters of war, individuals would conduct sacrifices to their name on battlefields, and other places where war had taken place.

The Iliad
There are many places within the Iliad, where Homer mentions the presence of Phobos and Deimos. Some are:

Homer, Iliad 11. 36 ff : "[The shield of Agamemnon:] And he took up the man-enclosing elaborate stark shield, a thing of splendour. There were ten circles of bronze upon it, and set about it were twenty knobs of tin, pale-shining, and in the very centre another knob of dark cobalt. And circled in the midst of all was the blank-eyed face of the Gorgo (Gorgon) with her stare of horror, and Deimos (Terror) was inscribed upon it, and Phobos (Fear).[3]

Homer, Iliad 15. 119 ff : "So he [Ares] spoke, and ordered Deimos (Terror) and Phobos (Fear) to harness his horses, and himself got into his shining armour."[4]