Cancer (constellation)

Cancer
Constellation
	List of stars in Cancer
Abbreviation	Cnc
Genitive	Cancri
Right ascension	9
Declination	+20
Area	506 sq. deg. (31st)
Meteor showers	Delta Cancrids;
Bordering; constellations	Lynx; Gemini; Canis Minor; Hydra; Leo; Leo Minor (corner);
	Visible at latitudes between +90° and −60°.; Best visible at 21:00 (9 p.m.) during the month of March.

In astronomy and astrology, Cancer (Latin for crab, symbol File:Cancer glyph.png, Unicode ♋) is one of the twelve constellations of the zodiac. Cancer is small and dim, and to many it does not resemble a crab. It lies between Gemini to the west and Leo to the east, Lynx to the north and Canis Minor and Hydra to the south.

Notable deep sky objects

Cancer is best noted among stargazers as the home of Praesepe (M44), an open cluster also called the Beehive Cluster or the Gate of Men, which contains the star ε Cancri. The smaller, denser open cluster M67 can be found here as well.

History

Etymology

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

Aratus called it Καρκινος (Karkinos), which Hipparchos 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.

Symbol

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

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

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. Bartschius 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 Hydra constellation, form the basis of the myth of the Lernaean Hydra, one of The Twelve Labours of Herakles, with which it is associated.

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 lucida being less than a 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).

In some cosmologies, Cancer is associated with the classical element Water, and thus called a Water Sign, forming Watery Trigon with Scorpio and Pisces. It is also one of the four cardinal signs (along with Aries, Libra, and Capricorn).

It is the domicile of the Moon or "House of the Moon", and this concept might originate from an ancient belief that Moon was located here at the creation of the world. Cancer is also the exaltation of Jupiter, and the traditional astrology claims it is the triplicity of Mars, one of the three lesser dignities which the modern astrology does not recognize.

Since Cancer is the opposite sign of Capricorn, which is the domicile of Saturn and the exaltation of Mars, Saturn naturally becomes detriment in Cancer, and Mars, although has the dignity of triplicity, becomes fall.

Many modern astrologers consider it to be significant that Pluto was discovered on the longitude of 20 degrees Cancer and the first atomic bomb was detonated at the moment when Saturn reached this longitude. Saturn is said to become particularly malefic in Cancer and Leo, for they are opposed to Saturn's own domiciles. Richard Saunders writes in Astrological Judgement and Practice of Physick (1677) that Black Plague of 1593 has been caused by transiting Saturn in Cancer, breeding "Flegm, thin Water, and Melancholy mixt".

Each astrological sign is assigned a part of the human body, viewed as the microcosmic counterpart of the heavenly signs. Cancer rules the breasts and belly. Caesius likened the sign to "the Breastplate of Righteousness" in Ephesians VI:14.

Elsbeth and Reinhold Ebertin extended this concept to that every single degree of 360 degrees of zodiac correlates to a specific part of human anatomy. In their Anatomische Entsprechungen der Tierkreisgrade (Anatomical Correspondences of the Zodiac Degrees, 1949), the section about Cancer starts with the 1 degree of Cancer correlating to the sixth rib, ends with the 30 degree of the sign correlating to the twelfth dorsal vertebra.

In the 1970s there was a proposal to rename the zodiac sign, as some astrologers felt that an imagined association with the disease Cancer was off-putting. Some people with the sun sign of Cancer refer to themselves as "Moonchild" instead, the sign being ruled by the Moon in astrology.

Alchemy

In the symbolism of alchemy, Cancer is related to the process of dissolution, i.e., a process by which a substance is dissolved in a liquid like an acid.

Notable and named stars

BD	F	Names and other designations	Mag.	Ly away	Comments
β	17	Beta Cancri, Tarf	3.53	290	< الطرف aţ-ţarf The eye (also limb)? or طرفة aţ-ţarfah The glance [of Leo]?
δ	47	Delta Cancri, Asellus Australis	3.94	136	< "The Southern Ass"
ι	48	Iota Cancri	4.03	298	binary star, component magnitudes 4.03, 6.58
α	65	Alpha Cancri, Acubens, Al Zubanah, Sertan	4.26	174	< الزبانة az-zubānah The claws/pincers < السرطان saraţān The crab
γ	43	Gamma Cancri, Asellus Borealis	4.66	158	< "The Northern Ass"
χ	18	Chi Cancri	5.13	59.1
	8	8 Cancri	5.14	211
ξ	77	Xi Cancri	5.16	381
ο¹	62	Omicron¹ Cancri	5.22	161
κ	76	Kappa Cancri	5.23
ρ²	58	Rho² Cancri	5.23
σ³	64	Sigma³ Cancri	5.23
μ	10	Mu Cancri	5.30
η	33	Eta Cancri	5.33
θ	31	Theta Cancri	5.33
π	82	Pi Cancri	5.36
	57	57 Cancri	5.40
τ	72	Tau Cancri	5.42
σ²	59	Sigma² Cancri	5.44
	60	60 Cancri	5.44
ν	10	Nu Cancri	5.45
	27	27 Cancri	5.56
φ¹	22	Phi¹ Cancri	5.58
	3	3 Cancri	5.60
A¹	45	45 Cancri	5.62
	15	15 Cancri	5.62
ζ^1,2	16	Zeta Cancri, Tegmen	5.63		double star, component magnitudes 6.02, 5.63 < tegmen, tegimen, tegumen The shell
b	49	49 Cancri	5.63
σ¹	51	Sigma¹ Cancri	5.67
ο²	63	Omicron² Cancri	5.68	160
υ¹	30	Upsilon¹ Cancri	5.71
ψ²	14	Psi² Cancri	5.73
	1	1 Cancri	5.80
ω	2	Omega Cancri	5.87
	66	66 Cancri	5.89
A²	50	50 Cancri	5.89
λ	19	Lambda Cancri	5.92
c	36	36 Cancri	5.92
d¹	20	20 Cancri	5.94
	29	29 Cancri	5.94
	75	75 Cancri	5.95
ρ¹	55	55 Cancri, Rho¹ Cancri	5.96		has 4 planets
	9	9 Cancri	5.96
	5	5 Cancri	5.99
	79	79 Cancri	6.04
	28	28 Cancri	6.05
	67	67 Cancri	6.07
d²	25	25 Cancri	6.11
	21	21 Cancri	6.11
	46	46 Cancri	6.12
	24	24 Cancri	6.22		double star, component magnitudes 6.51 7.81
	12	12 Cancri	6.25
	53	53 Cancri	6.25
	61	61 Cancri	6.25
ε	41	Epsilon Cancri	6.29		member of the Praesepe or Beehive Cluster; originally the ε designation applied to the entire cluster
φ²	23	Phi² Cancri	6.30
	4	4 Cancri	6.32
υ²	32	Upsilon² Cancri	6.35
	54	54 Cancri	6.36
	39	39 Cancri	6.39
ψ¹	13	Psi¹ Cancri	6.44
	34	34 Cancri	6.48
	81	81 Cancri	6.49
	37	37 Cancri	6.54
	35	35 Cancri	6.55
	40	40 Cancri	6.61
	83	83 Cancri	6.61
	38	38 Cancri	6.65
	70	70 Cancri	6.67
	80	80 Cancri	6.87
	52	52 Cancri	7.63
	74	74 Cancri	7.69
		DX Cancri	14.81		nearby

Source: The Bright Star Catalogue, 5th Revised Ed., The Hipparcos Catalogue, ESA SP-1200

References

Star Names: Their Lore and Meaning, by Richard Hinckley Allen, Dover. ISBN 0486210790
Dictionary of Symbols, by Carl G. Liungman, W. W. Norton & Company. ISBN 0393312364
Astrological Judgement & Practice of Physick, by Richard Saunders, Astrology Classics. ISBN 1538101122

External links

The Deep Photographic Guide to the Constellations: Cancer