Lernaean Hydra that Hera placed the Hydra and crab as constellations in the night sky after Heracles slew him. When the sun is in the sign of Cancer (Latin for "The Crab"), the constellation Hydra has its head nearby. In fact, both constellations derived from the earlier Babylonian signs: Bashmu ("The Venomous Snake") and Alluttu ("The Crayfish"). Primary sources Secondary sources Lernaean Hydra The Lernaean Hydra or Hydra of Lerna (, "Lernaîa Hýdra"), more often known simply as the Hydra, is a serpentine water monster in Greek and Roman mythology. Its lair was the lake of Lerna in the Argolid, which was
HMS Hydra (A144) the first commission of HMS "Hydra". She was decommissioned and sold to the Indonesian Navy in 1986 and renamed KRI "Dewa Kembar" (Pennant Number 932); she was still in service in 2006. There have been eight ships of the name in the Royal Navy, named for the Hydra of Greek Mythology, a serpent with many heads (though nine is generally accepted as standard), the centre one of which was immortal. The monster was overcome and slain by Hercules. The ship's badge of HMS "Hydra" depicts the monster with seven heads. The ship's motto was "Ut Herculis Perseverantia" ("Like Hercules Persevere").