Cancer (♋) is the fourth astrological sign in the Zodiac, originating from the constellation of Cancer. It spans 90° and 120° celestial longitude. Under the tropical zodiac, the Sun transits this area between approximately June 21 and July 23, and under the sidereal zodiac, the Sun transits this area between approximately July 16 and August 15. In astrology, Cancer is the cardinal sign of the Water trigon, which is made up of Cancer, Pisces, and Scorpio. It is considered a negative sign, whose domicile, or ruling planet, is the Moon.
Though some depictions of Cancer feature a lobster, asin the illustration from the 1390 De Grey Book of Hours at right, the sign is most often represented by the crab, based on the Karkinos, a giant crab that harassed Heracles during his fight with the Hydra. In ancient times, Cancer was known as the “dark sign” because of the obscured visibility of its constellation in the night sky.
In astrology, Cancer is said to be the house of Neptune and the exaltation of Jupiter, both astronomical bodies having influence over those born under Cancer. In Vedic astrology the sign is named Karka and its Lord is Moon. Note the similarity between the sign and the name of the crab. The story of Cancer the Crab is said to be connected to Heracles or Hercules as he was called by the Romans and more commonly referred to. Some storytellers say that during Hercules’ fight with Lernaean Hydra, the multiple-headed monster, the goddess Hera sent a crab from a swamp to snap at Hercules’ feet to distract him. Hera had sworn to kill Hercules but that belongs to another story. Hercules was able to kill the crab by crushing its shell with his foot and also managed to defeat the Hydra. Hera, thwarted because Hercules had slain the beast she raised to kill him, placed it in the dark blue vault of the sky as the constellation Hydra. In spite of the fact the crab failed to help defeat Heracles, it too was rewarded by Hera. She turned the crab into the constellation Cancer.
In Chinese star lore, Cancer is in the 23rd of the 28 mansions or xiu. This mansion is called Gui which roughly translates to “ghosts”. The Chinese divided the sky into four quarters, each with its own direction, season, and mythical creature. Cancer exists in the Red (Vermillion) Bird of the south. It is associated with summer.
Cancer as Archetype
Cancer is the cardinal water sign, and it’s archetypes are ones of nurturing, domesticity and fertility. A main archetype of Cancer is the Mother. This is the mother as our protector and guide, the ruler of the home. Cancer is also a symbol of the home itself, as represented by those creatures who carry their homes with them,the turtle, the lobster and the crab. Having a place to call home, where we are secure, is integral to a solid sense of well-being. Any success in the world is dependent on having a place for rest and rejuvenation, otherwise we would exhaust ourselves, always needing to be “on”.
In astrological terms a zodiac sign follows the sign before it and grows out of it, and is its fulfillment and completion in a sense. So Leo, a very bold and extroverted sign which follows Cancer, is able to be so because Cancer has created a secure home and base from which to strike forth. Since the ruler of Cancer is the Moon, Cancer also represents the unconsciousness, the fluid and mysterious part of the mind that speaks to us in dreams and symbols. This is illustrated by the lobster coming out of the pool in the Moon card from the Rider Waite tarot deck at right. The complicated symbolism of the card is more easily understood when this piece of shorthand is translated. Usually the card is associated with Pisces, another water sign, but the Cancer aspect and archetype are in there as well.