The Legends of Cancer and Leo: The Extraordinary Adventures of Hercules

Every July, the skies are graced by both Cancer and Leo, two constellations whose origins are deeply intertwined with the legendary tales of Greek mythology. This month, we explore the captivating stories behind these celestial signs, both connected to the most celebrated hero of ancient Greece: Heracles, known to the Romans as Hercules. To understand Greek and Roman mythology without knowing Hercules would be like exploring Chinese mythology without encountering the Monkey King—an essential piece of the puzzle would be missing.

The Divine Family Drama

Before diving into the myths, it’s crucial to unravel the complex web of relationships that define these stories. At its heart, Greek mythology often revolves around the affairs of Zeus, the king of the gods. Whether it’s the Twelve Labors of Hercules or the epic Trojan War, many of these tales stem from the power struggles among Zeus’s descendants.

The Birth of a Hero

In a previous exploration of Greek myths, we discussed Perseus, another renowned hero. Following his lineage, Perseus married Andromeda, an Ethiopian princess, and they had a son named Electryon. Electryon later wed Eurydice, daughter of Pelops, and together they had a daughter, Alcmene. Alcmene grew up to catch the eye of Zeus himself, and from their union came the mighty Hercules. This branch of the family tree flourished in Thebes.

Meanwhile, in Argos, another thread unfolded. Perseus had another son, Sthenelus, who married Nicippe, another daughter of Pelops. Among their children was Eurystheus, who would become the king of Mycenae.

Thus, the stage was set. Both Hercules and Eurystheus were descendants of Perseus and Pelops, though their generations differed: Eurystheus was a grandson of Perseus, while Hercules was a great-grandson, making Eurystheus the elder. But what conflict arose between them, and how does it connect to the constellations of Cancer and Leo?

The Divine Decree and Hera’s Jealousy

Zeus held a profound affection for Alcmene, with some myths suggesting she was his last mortal lover. When Alcmene became pregnant, Zeus declared from Mount Olympus that the child born on a certain day would rule over the entire house of Perseus. This meant dominion over the Peloponnese peninsula, a realm of immense power and prestige.

No one dared oppose Zeus—except for one: Hera, the queen of the gods and Zeus’s wife. Known for her relentless jealousy, Hera had made it her mission to persecute Zeus’s lovers and illegitimate children. She had already tormented Io, and now she set her sights on Alcmene’s unborn son, Io’s thirteenth-generation descendant.

Hera raced to Argos in her golden chariot and used her divine power to force Nicippe into premature labor. The child born that day was Eurystheus. With his birth, Zeus’s prophecy was fulfilled, but not as intended: Eurystheus, not Hercules, would rule the Peloponnese. Hercules, Zeus’s beloved son, would instead serve Eurystheus. Though Zeus realized Hera’s deception, it was too late to reverse the decree. He could only extract a promise from Hera to cease her persecution of Hercules.

The Rivalry and the Twelve Labors

As the two boys grew, they learned of the prophecy. Eurystheus, frail from his premature birth, resented Hercules, who was already renowned for his incredible strength. Consumed by envy, Eurystheus sought ways to eliminate Hercules. Protected by Zeus, however, Eurystheus could not act directly. Instead, he devised a series of impossible tasks, hoping they would lead to Hercules’s demise. These tasks, originally ten but later expanded to twelve, became the famous Twelve Labors of Hercules—and the origins of two constellations.

The Origin of Leo

The first labor tasked Hercules with slaying the Nemean Lion, a fearsome beast terrorizing the countryside of Argos. While others saw certain death, Hercules fearlessly ventured into the forest armed only with his olive-wood club.

As night fell, the Nemean forest grew dark and foreboding, filled with the sounds of wild animals. Hercules remained vigilant, his senses sharp. Soon, the lion appeared, its belly full from a recent kill. Enraged, Hercules charged, firing three arrows at the beast. To his astonishment, the arrows bounced off the lion’s hide as if it were stone. Undeterred, Hercules swung his club, striking the lion squarely on the head. The lion staggered, and before it could recover, Hercules leaped onto its back, strangling it with his bare hands until it lay still.

Unable to carry the entire lion back, Hercules skinned it and wore its pelt as armor, a symbol of his strength for the rest of his life. To honor this triumph, Zeus placed the lion among the stars, creating the constellation Leo.

The Origin of Cancer

The second labor required Hercules to defeat the Hydra, a multi-headed serpent. Confident after his victory over the lion, Hercules engaged the monster in battle. Hera, ever spiteful, sent a giant crab to aid the Hydra. The crab clamped onto Hercules’s leg with its powerful claws, attempting to immobilize him. In a fit of rage, Hercules crushed the crab with his club, reducing it to fragments.

Though the crab failed in its mission, Hera honored its loyalty by placing it in the sky as the constellation Cancer.

The Tragic Twist of Fate

The deeper significance of this labor lies not in the crab’s intervention but in the Hydra’s blood. After slaying the serpent, Hercules dipped his arrows in its poisonous blood. Years later, one of these arrows would accidentally kill Nessus, a centaur. With his dying breath, Nessus deceived Hercules’s wife, Deianira, into believing his blood could restore her husband’s love. She preserved it, unaware of its toxicity.

Years later, she gave Hercules a robe soaked in this poisoned blood, hoping to win back his affection. Instead, it caused the great hero’s agonizing death—a tragic end foreshadowed by the very tasks that made him legendary.

The tales of Cancer and Leo are but fragments of Hercules’s extraordinary life, a testament to his strength, resilience, and the complexities of divine intrigue. These myths remind us that even the stars above are woven with stories of heroism, betrayal, and destiny.