Gemini is the third astrological sign in the Zodiac, originating from the constellation of Gemini. Stories of hero twins are also related throughout the world. For the Greeks their was Castor and Polydeuces, also known as the Dioscuri, or Heavenly Twins. They were the children of Zeus and Leda, queen of Sparta, thus also the brothers to the infamous Helen, late of Troy. The exploits of these twins are many, and all heroic. In their youth they sailed with Jason to retrieve the Golden Fleece. Later they very heroically fought the famous Trojan War and came victorious. Helena, their sister, was brought back home to her husband Menelaus. Later they fell in love with the daughters of Leudippus and challenged their suitors Idas and Lynceus to fight with them.
Both Idas and Lynceus were killed but Castor couldn't survive either. A grieved Pollux tried committing suicide but being an immortal failed to die. He begged his father Jupiter to revive his brother who obliged, but not on earth, rather in heavens as the two stars named Pollux and Castor in the constellation that Gemini in the zodiac. The twins were also associated with commerce and were akin to Hermes (whom the Romans identified with Mercury, ruler of Gemini) another son of Zeus. Hermes was a mischievous infant who was the Messenger of the Gods as well as being the God of travellers and Commerce. Often perceived as twin boys, the lore sustains that they were placed in the night sky by Jove to honor and exemplify the fidelity of their brotherly love. In other instances they were seen as a sister and brother or two angels, then within later Christian traditions, as Adam and Eve.