Hydra
Sea Serpent (Hydrae)
Hydra, the Water Snake, is the largest of all 88 constellations, stretching across a quarter of the sky from Libra to Cancer. This serpentine constellation lies south of the ecliptic and takes over six hours to fully rise. Despite its size, Hydra contains only one bright star, Alphard, called 'the Solitary One' because it lies in a relatively barren region of the sky.
📜 Mythology
Hydra represents the multi-headed Lernaean Hydra slain by Hercules as his second labor. This monstrous serpent had multiple heads (some accounts say nine, others a hundred), and when one was cut off, two more grew back. Hercules eventually defeated it by having his nephew Iolaus cauterize each neck stump with fire after decapitation. Hydra is also connected to the myth of Apollo's crow and cup (Corvus and Crater), which sit upon the serpent's back.
💡 Facts
- ✦Hydra is the largest constellation, covering 1,303 square degrees - 3.16% of the entire sky
- ✦Alphard means 'the solitary one' in Arabic, as it appears alone in a relatively star-poor region
- ✦M83, the Southern Pinwheel Galaxy, is one of the closest and brightest barred spiral galaxies