Hydra

Hydra is the largest of all 88 constellations, stretching over 100 degrees across the sky. Despite its enormous size, it has only one bright star, Alphard, the Solitary One. It contains M83 (the Southern Pinwheel Galaxy) and the Ghost of Jupiter planetary nebula.

Location in the Sky

When to Observe

Hydra is best observed during April. It is located in the SQ2 quadrant and is primarily visible from the both hemispheres. The constellation contains 17 main stars forming its asterism, with 49 Bayer/Flamsteed designated stars in total. Its brightest star is Alphard.

Mythology & History

In Greek mythology, Hydra represents the Lernaean Hydra, a multi-headed water serpent slain by Heracles as the second of his twelve labors. Each time he cut off one head, two more grew in its place. He finally defeated it by cauterizing the neck stumps with fire.