Hydra

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Contents of this page: | Description | Skylore | Modern Culture | Origin and History | Star Clusters | Galaxies | Submit new info... |

Images (at bottom of page): | Hydra Chart: (Figure 1) | Hyginus, 1482, page F4r: (Figure 2) | Bayer, 1661, page zUU: (Figure 3) | Bayer, 1697, page N3r: (Figure 4) | Bayer, 1697, page N3v: (Figure 5) | Bayer, 1697, page N4r: (Figure 6) | Bode, 1801, page l: (Figure 7) | Bode, 1801, page r: (Figure 8) | Bode, 1801, page l: (Figure 9) | Bode, 1801, page l: (Figure 10) | Bode, 1801, page r: (Figure 11) | Aspin, 1825, page Hydra: (Figure 12) | Images digitized by Hannah Magruder.

Constellation Data

• Name: Hydra
• Translation: Sea serpent
• Abbreviation: Hya
• Genitive: Hydrae (What is the Genitive form?)
• Size: 1 of 88
• Located between: Antlia, Argo Navis, Cancer, Canis Minor, Centaurus, Corvus, Crater, Leo, Libra, Monoceros, Puppis, Pyxis, Sextans, Virgo
• RA: 11 hours. (What is Right Ascension?)
• Decl: -15 degrees. (Is this constellation ever visible from my latitude? What is Declination?)
• Season: Spring
• Midnight Culmination: March 15 (Where should I look for a constellation on a date before or after its midnight culmination? What is Midnight Culmination?
• References: Chet Raymo, 365 Starry Nights, 38,43,52,53.

Description

The largest and longest of the constellations, stretching from Cancer to Libra. Its brightest star is Alphard, with an orangish tint. Two constellations ride it, Crater (cup) and Corvus (crow).

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Skylore and Literature

Hercules was sent to kill Hydra, a sea monster which possessed the terrifying ability, whenever a head was cut off, to grow two heads in its place.

Cicero, De natura deorum, II.110, trans. of Phenomena by Aratos of Soli (ca. 220 B.C.):

Here Hydra rises from the nether realms, | And in her midmost coil the Wine-bowl (Crater) gleams, | While pressing at her tail the feathered Crow (Corvus) | Pecks with his beak; and here, hard by the Twins, | The Hound’s forerunner, in Greek named Prokyon.

• Please submit Skylore suggestions to Laura Gibbs.
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Modern Culture

• Books: (Book list maintained by JoAnn Palmeri).
• Movies: Internet movie database. (Movie list maintained by Sylvia Patterson).
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Origin and History

Hydra is included in the ancient star catalogs of Eudoxos of Knidos, Aratos of Soli, and Ptolemy.

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Star Clusters

M48 (Galactic cluster), mag. 6.0.

M68 (Globular cluster), mag. 8.2.

• What are Star Clusters?
• Dolan Hydra page.
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Galaxies

M83 (Spiral galaxy), mag. 7.6.

• What are Galaxies?
• Table of Messier Objects.
• What is apparent Magnitude?
• Dolan Hydra page.
• National Optical Astronomy Observatory (NOAO) Galaxy images
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Submit new info...

Many excellent websites provide a variety of information about constellations for amateur astronomers and telescope users (see sidebar links for a few of these). These constellation pages are not intended to duplicate those efforts, but are devoted to two aims: First, they are intended to assist the beginning skywatcher, including students in history of science survey courses, in becoming familiar with Basic Celestial Phenomena (BCP). Second, these pages are devoted to the history of the constellations and the history of astronomy. They are intended to serve as a repository for collaborative use and reference. Do you have additional historical information about the stars or constellation described on this page? Please submit additional information to kmagruder@ou.edu. Submissions will be attributed. Editors for historical information are Kerry Magruder, JoAnn Palmeri, Peter Barker, and Laura Gibbs.

Oklahoma History of Science exhibits: http://hsci.cas.ou.edu/exhibits/. Page revised 4/15/04

Bad links, misplaced images, or questions? Contact Kerry Magruder. Thank you.

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"If the stars should appear one night in a thousand years, how would men believe and adore, and preserve for many generations the remembrance of the city of God which had been shown. But every night come out these envoys of beauty, and light the universe with their admonishing smile." R. W. Emerson, Nature

Images

Exhibit credit: Kerry Magruder.