The Hydra is the biggest constellation in the sky. It is so long it takes 6 hours to rise completely. A Hydra is a water snake. It lies in the southern hemiphere. It was inclueded in the conselation group in the 2nd centry.
The Hydra Constellation as an adapted Babylonian Constellation. The Hydra is the 2nd Heracles' labor in Greek Myth. In Mythology the Hydra had 9 heads and 1 was immortal. Herclues defeated the Hydra by first shooting a flaming arown and the Hydra lair smoked out. He burned the 8 heads and cut off the 9th one and buried it under a rock