Hydra (constellation)

Hydra
Constellation
Hydra
AbbreviationHya
GenitiveHydrae
Pronunciation
Symbolismthe sea serpent
Right ascension8h 10m 56.2029s15h 02m 31.3847s
Declination6.6302376° – −35.6938896°
QuadrantSQ2
Area1303 sq. deg. (1st)
Main stars17
Bayer/Flamsteed
stars
75
Stars with planets18
Stars brighter than 3.00m2
Stars within 10.00 pc (32.62 ly)4
Brightest starAlphard (α Hya) (1.98m)
Messier objects3
Meteor showers
  • Alpha Hydrids
  • Sigma Hydrids
Bordering
constellations
Visible at latitudes between +54° and −83°.
Best visible at 21:00 (9 p.m.) during the month of April.

Hydra is the largest of the 88 modern constellations, measuring 1303 square degrees, and also the longest at over 100 degrees. Its southern end borders Libra and Centaurus and its northern end borders Cancer.[1] It was included among the 48 constellations listed by the 2nd century astronomer Ptolemy. Commonly represented as a water snake, it straddles the celestial equator.

  1. ^ Ridpath & Tirion 2001, pp. 158–160.