13 December 2014

Constellation Families

List of Constellation Families

The 88 constellation families are divided into eight groups or families. Some are purely in the northern hemisphere (like the Ursa Major Family) and some are soley above the ecliptic - the apparent path of the sun against the background stars - (like the Bayer Family and the La Caile Family). The Perseus Family would be completely above the ecliptic if it wasn't for the tail of Cetus dipping into the south.

Most would recognise the Zodiac Family, the constellations on the ecliptic, in front of each of which the sun goes in turn in the course of a year. Of the three others, the Hercules Family is surely the most Herculean, with 9/10 constellations north of the ecliptic, and a further 9 south of it, making it the biggest of them all. Then we have the smallest group, the Orion Family, with a mere five constellations...a small family for such an important and recognisable constellation character in the heavens...
...and talking of heavens, the last to be mentioned constellation family is the Heavenly Waters Family, most of which (except Equuleus, the horse) are to do with water.

Here is a list of the eight constellation families and their members, starting at the North Pole and (roughly) and working south:

The Ursa Major Family

(image: The Ursa Major Constellation Family

Ursa Minor (lesser Bear / Little Dipper)
Draco (dragon)
Camelopardalis (giraffe)
Ursa Major (Greater Bear; containing asterism Big Dipper / The Plough)
Boötes (bear driver or herdsman)
Canes Venatici (hunting dogs)
Lynx (lynx)
Corona Borealis (northern crown)
Leo Minor (lesser Lion)
Coma Berenice (Egyptian Queen Berenice)

The Perseus Family 

Image: The Perseus Constellation Family

Cepheus (Cassiopeia's royal consort)
Cassiopeia (Lady of the Chair)
Auriga (Charioteer)
Lacerta (Lizard)
Triangulum (Triangle)
Pegasus (see Eridanus)
Cetus (whale) [the only one of this family below the ecliptic and below the zodiac family, and for some reason is also sometimes listed in the 'Heavenly Waters' family]

The Hercules Family

Image: The Hercules constellation Family

North of the ecliptic (and of the zodiac family)

Cygnus (swan; sometimes called the Northern Cross)
Lyra (lyre)
Vulpecula (fox)
Sagitta (arrow)
Serpens cauda (snake's body) and Serpens Caput (snake's head)
Aquila (eagle)
Scutum (shield)
Ophiuchus (snake bearer/god of medicine & healing) [see note on Ophiuchus, below 'Zodiac Family']

South of the ecliptic (and of the zodiac family):

Sextans (sextant)
Hydra (sea snake)
Crater (cup)
Corvus (crow)
Lupus (wolf)
Corona Australis (southern crown)
Ara (altar)
Triangulum Australis (southern Triangle)

The Zodiac Family

Image: The Zodiac Constellation Family

(This is the family on the ecliptic, the apparent path through which the sun travels as the Earth moves in its orbit around it.)

Aquarius (water carrier)
Capricorn (goat)
Sagittarius (archer)
Scorpius (scorpion)
Libra (scale)
Virgo (virgin)
Leo (lion)
Cancer (crab)
Gemini (twins)
Taurus (bull)
Aries (ram)
Pisces (fishes)

To remember the zodiac constellation order, Isaac Watts (1674-1748) wrote:

    The RAM, the BULL, the heavenly TWINS,
    And next the CRAB, the LION shines,
    The VIRGO and the SCALES;

    The MAN who pours the water out
    And FISH with glittering tails.

I prefer this rhyme by E. Cobham Brewer (1810-1897):

    Our *vernal signs the RAM begins,
    Then comes the BULL, in May the TWINS;
    The CRAB in June, next LEO shines,
    And VIRGO ends the northern signs.

    The BALANCE brings autumnal fruits,
    The SCORPION stings, the ARCHER shoots;
    December's GOAT brings wintry blast,
    AQUARIUS rain, the FISH comes last.

    (*vernal = of/in the season of Spring) 

[Interestingly, and an argument against astrology, sometimes called the 'thirteenth sign of the zodiac', the constellation of Ophiuchus should actually now be included in this family, since the sun actually passes through it (17 days) for longer than it is in Scorpius (5 days)].

The Orion Family

Image: The Orion Constellation Family

Orion (hunter)
Canis Minor (lesser dog)
Monoceros (unicorn)
Canis Major (greater dog)
Lepus (hare)

The Heavenly Waters Family

Image: The Heavenly Waters Constellation Family

The first two of this family are actually separated from the others, and lie above the zodiac constellations, surrounded by Velpecula to the North: Aquarius to the South; and Pegasus and Aquila to the East and West:

Delphinus (dolphin)
Equuleus (horse)

Separated from the rest of the family, but on the other side of the Zodiac constellations, is:

Pisces Austrinus (southern fish)

The next two are related to Jason's great ship, Argo, as a river he sailed on, and the dove at the stern:

Eridanus (river)
Columba (dove)
 The great ship Argo was divided into the following four constellations:

Carina (keel / hull of ship)
Puppis (Stern / poop-deck of ship)
Vela (sails of the ship)
Pyxis (mariner's compass (formerly the ship's mast)

The Bayer Family

Image: The Bayer Constellation Family

Seventeenth century astronomer, Johann Bayer, introduced this group of creatures, and so it was named after him:

Grus (crane)
Phoenix (phoenix)
Tucana (toucan)
Indus (indian)
Pavo (peacock)
Apus (bird of paradise)
Musca (fly)
Chamaeleon (chameleon)
Volans (flying fish)
Dorado (goldfish)
Hydrus (water Snake)

The La Caille Family

Image: The La Caile Constellation Family
(their position marked on this map, though these modern constellations
were not conceived at the time this map was made!)

This group was named in 1756 by a well-known astronomer, Nicolas Louis de Lacaille , who called most of them (not Mensa) by scientific instrument names. Many of these were used to fill in poor star regions not filled by other family constellations, or far south where the Greeks and Romans couldn't see so hadn't mapped:

Antlia (air pump)

Microscopium (microscope)
Telescopium (telescope)

Fornax (furnace)
Sculptor (sculptor's apparatus)

Norma (the level)
Circinus (compass)

Caelum (graving tool)
Pictor (easel)
Horologium (clock)
Reticulum (net)

Mensa (originally Mons Mensa = Table Mountain at Capetown, S. Africa, where  La Caille's observatory then was)
Octans (octant)

This colour-coded constellation map, used in an earlier post on the 88 modern constellations, shows the families so well:

(image: constellation map: Wikipedia)

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