Cancer (constellation)

Infobox Constellation
name = Cancer
abbreviation = Cnc
genitive = Cancri
symbology = the Crab
RA = 9
dec= +20
areatotal = 506
arearank = 31st
numbermainstars = 5
numberbfstars = 76
numberstarsplanets = 1
numberbrightstars = 0
numbernearbystars = 2
brighteststarname = β Cnc (Altarf)
starmagnitude = 3.5
neareststarname = DX Cnc
stardistance = 11.8 | numbermessierobjects = 2
meteorshowers = Delta Cancrids
bordering = Lynx
Gemini
Canis Minor
Hydra
Leo
Leo Minor (corner)
latmax = 90
latmin = 60
month = March
notes=

Cancer (pron-en|ˈkænsɚ, _la. crab, symbol to the south.

Planetary system

55 Cnc is a quintruple planet system with four gas giants and one terrestrial planet.

Notable deep sky objects

Cancer is the best noted among stargazers as the home of Praesepe (Messier 44), an open cluster also called the "Beehive Cluster" or the "Gate of Men", which contains the star ε Cancri. The smaller, denser open cluster Messier 67 can be found here as well.

History

Cancer, the Crab, plays a minor role in the Twelve Labors of Hercules. While Hercules was busy fighting the multi-headed monster, Hydra, the goddess Hera, who did not like Hercules, sent the Crab to distract him. Cancer grabbed onto the hero's toe with its claws, but barely breaking the rhythm of his great battle with Hydra, Hercules crushed the crab with his foot. Hera, grateful for the little crustacean's heroic but pitiful effort, gave it a place in the sky. The crab did not win, so the gods didn't give the crab bright stars.

Named Stars

Etymology

The early Sanskrit name of this constellation was "Karka" and "Karkata", in Telugu "Karkatakam", Kannada "Karkataka" or "Kataka" , Tamil "Karkatan", and the Sinhalese "Kagthaca".The later Hindus knew it as "Kulira", from "Κολουρος" ("Koloyros"), the term originated by Proclus.

Aratus called it "Καρκινος" ("Karkinos"), which Hipparchus and Ptolemy followed, the "Carcinus" of the "Alfonsine tables" being Latinized form of the Greek word. Eratosthenes extended this as "Καρκινος", "Ονοι", "και Φατνη": the Crab, Asses, and Crib.

"Litoreus", Shore-inhabiting, is from Manilius and Ovid. "Astacus" and "Cammarus" appear with various classic writers. "Nepa" is from Cicero's "De Finibus" and the works of Columella, Plautus, and Varro - all signifying Crab, Lobster, or Scorpion.

Kircher said that in Coptic Egypt it was "Κλαρια", the "Bestia seu Statio Typhonis", the Power of Darkness. Jérôme Lalande identified this with Anubis, one of the Egyptian divinities commonly associated with Sirius.

ymbol

The modern symbol for Cancer is the crab, but it has been represented with various types of creatures, usually those living in the water, and always those with an exoskeleton, decapods in particular.

In the Egyptian records of about 2000 BC it was described as Scarabaeus (Scarab), the sacred emblem of immortality, although Peter Jensen claimed this sign had been a tortoise in Babylonia, and that it was so figured there and in Egypt 4000 BC.

In the 12th century, an illustrated astronomical manuscript shows it as a water beetle. Albumasar writes of this sign in the work published in 1489 as a large crayfish. Jakob Bartsch and Stanislaus Lubienitzki, in the 17th century, described it as a lobster.

Mythology

As the constellation vaguely resembles a crab, it may, together with the constellation Hydra, form the basis of the myth of the Lernaean Hydra, one of The Twelve Labours of Hercules, with which it is associated. Many people debate whether it is a crab or lobster.who

Cancer is said to have been the place for the Akkadian Sun of the South, perhaps from its position at the winter solstice in very remote antiquity. But afterwards it was associated with the fourth month "Duzu" (June-July in the modern western calendar), and was known as the Northern Gate of Sun.

Showing but few stars, and its brightest stars being of only 4th magnitude, it was often considered "Dark Sign", quaintly described as black and without eyes. Dante, alluding to this faintness and position of heavens, wrote in "Paradiso":

"Thereafterward a light among them brightened,
"So that, if Cancer one such crystal had,
"Winter would have a month of one sole day."

Astrology

The Western astrological sign Cancer of the tropical zodiac (June 21–July 22) differs from the astronomical constellation and the Hindu astrological sign of the sidereal zodiac (July 21–August 9).

References

*"Star Names: Their Lore and Meaning", by Richard Hinckley Allen, Dover. ISBN 0-486-21079-0
* Ian Ridpath and Wil Tirion (2007). "Stars and Planets Guide", Collins, London. ISBN 978-0007251209. Princeton University Press, Princeton. ISBN 978-0691135564.
*"Dictionary of Symbols", by Carl G. Liungman, W. W. Norton & Company. ISBN 0-393-31236-4

External links

* [http://www.allthesky.com/constellations/cancer/ The Deep Photographic Guide to the Constellations: Cancer]
* [http://www.ianridpath.com/startales/cancer.htm Star Tales – Cancer]