The 88 Constellations: A Complete Beginner's Guide to the Night Sky

Go outside tonight, look up, and you are looking at one of 88 named regions of
sky. Every star you can see, every planet, every galaxy and nebula, belongs to
one of them. There is no leftover space and no overlap: the 88 constellations
tile the entire celestial sphere.

This guide is the starting point for all of them. It explains what a
constellation actually is, how to read the sky well enough to find things, and
then links to a full write-up of every one of the 88 — how to find it, what it
looks like, the stars inside it, the story behind the name, and what you can see
with your eyes, binoculars or a telescope.

You do not need equipment to start. You do not need to be somewhere dark. You
need to be able to find one pattern you recognise, and work outwards from there.

What a constellation actually is

Most people think a constellation is a pattern of stars. That is how they began,
but it is not what they are now.

Since 1922 a constellation has been an area of the sky — a region with
precise borders, like a country on a map. The International Astronomical Union
fixed the list at 88, and in 1930 the Belgian astronomer Eugène Delporte drew
the boundaries, following lines of right ascension and declination so that every
point in the sky falls inside exactly one constellation.

That change matters more than it sounds. When astronomers say a comet is "in
Taurus", they do not mean it is sitting among the bull's stars — they mean its
position falls within Taurus's borders. The stars of a constellation are usually
nothing to do with each other either: they sit at wildly different distances and
simply happen to line up from where we stand. Orion's Belt looks like three
evenly spaced stars in a row, but they are hundreds of light years apart.

Constellation or asterism?

A pattern that is not one of the official 88 is an asterism. The distinction
trips people up constantly, because several of the most famous shapes in the sky
are asterisms rather than constellations:

• The Big Dipper (or Plough) is an asterism inside the constellation Ursa Major.
• The Summer Triangle is an asterism spanning three constellations — Lyra, Cygnus and Aquila.
• The Teapot is an asterism inside Sagittarius.
• The Winter Hexagon stretches across six constellations at once.

Asterisms are often easier to learn than the constellations that contain them,
and they make excellent signposts. Use them.

Where the names came from

The 88 arrived in three waves, and you can date almost any constellation by
looking at what it depicts:

• The ancient 48. Mesopotamian and Greek figures, catalogued by Ptolemy around 150 AD — gods, heroes, animals and the zodiac. These have the brightest stars, because they were named by people choosing what stood out.
• The southern additions, 1590s–1600s. Dutch navigators Pieter Dirkszoon Keyser and Frederick de Houtman charted the far southern sky on trading voyages, naming constellations after exotic animals: a toucan, a peacock, a bird of paradise, a chameleon, a flying fish.
• The Enlightenment instruments, 1750s. Nicolas-Louis de Lacaille catalogued nearly 10,000 southern stars from the Cape of Good Hope and filled the remaining gaps with the tools of science — a telescope, a microscope, a pendulum clock, an air pump, a set of compasses.

Between those waves, astronomers like Johannes Hevelius added faint filler
constellations between the famous ones — the lynx, the little fox, the lizard.
Many other proposals were made and later abolished, including several dedicated
to kings and patrons. The 1922 settlement kept 88 and discarded the rest.

How to read the night sky

Five ideas will get you most of the way. None of them require equipment.

Magnitude: how bright is bright?

Star brightness is measured in magnitude, on a scale that runs backwards:
lower numbers mean brighter stars. It is confusing at first and then becomes
second nature.

• Magnitude −1.5: Sirius, the brightest star in the night sky
• Magnitude 0 to 1: the brightest couple of dozen stars — Vega, Arcturus, Rigel
• Magnitude 2 to 3: the stars that make up most constellation patterns
• Magnitude 4 to 5: visible from a dark suburb, gone from a city
• Magnitude 6: roughly the naked-eye limit under genuinely dark skies

Each step of 1 magnitude is about 2.5 times the brightness. When a constellation
write-up says "nothing brighter than magnitude 4", that is a warning that you
will need to get away from streetlights.

Right ascension and declination: the sky's grid

Declination is the sky's version of latitude, measured in degrees north (+)
or south (−) of the celestial equator. Right ascension is the sky's
longitude, measured in hours from 0 to 24. Together they pin any object to a
fixed point.

The practical value is declination. A constellation at declination −60° is a
southern object and northern observers will struggle or fail. One near 0° sits
on the celestial equator and is visible from essentially everywhere on Earth.

Which constellations can you see?

This depends entirely on your latitude, and it is the single biggest factor in
what is available to you.

• From the northern hemisphere you can see the northern sky plus a decreasing slice of the southern one. Crux, Carina and the Magellanic Clouds are simply unavailable.
• From the southern hemisphere the reverse applies — no Polaris, no Ursa Minor, and the Big Dipper skims the horizon at best.
• From near the equator you get almost everything across a full year, which is the best deal available.

Constellations near your celestial pole are circumpolar: they never set, and
you can see them any clear night of the year.

When to look

Every constellation has a month when it sits highest in the evening sky. Look
six months either side and it will be up during the day, invisible. The tables in
each write-up give a "best seen at 9 pm" month — treat it as the centre of a
window that runs roughly two months either side.

Start with what you can already find

The most useful skill in astronomy is star hopping: finding something you
know, then using it as a pointer to something you do not.

• Find the Big Dipper, and its two end stars point to Polaris.
• Follow the Dipper's handle in an arc to Arcturus, then spike on to Spica.
• Find Orion's Belt, follow it down-left to Sirius and up-right to Aldebaran.
• From the Southern Cross, extend the long axis four and a half times to find south.

Learn three or four of these and the whole sky opens up.

The eight constellation families

The 88 are traditionally sorted into eight families — groups that share a
region of sky, a mythological story, or a moment of history. This is the most
useful way to learn them, because constellations in a family are neighbours: find
one and the others are close by.

The Ursa Major family (10 constellations)

The circumpolar northern group anchored by the Big Dipper.

Boötes, Camelopardalis, Canes Venatici, Coma Berenices, Corona Borealis, Draco, Leo Minor, Lynx, Ursa Major, Ursa Minor.

The Zodiac family (12 constellations)

The twelve constellations the Sun, Moon and planets travel through.

Aquarius, Aries, Cancer, Capricornus, Gemini, Leo, Libra, Pisces, Sagittarius, Scorpius, Taurus, Virgo.

The Perseus family (9 constellations)

The northern sky's Andromeda myth, told across nine constellations.

Andromeda, Auriga, Cassiopeia, Cepheus, Cetus, Lacerta, Pegasus, Perseus, Triangulum.

The Hercules family (19 constellations)

The largest family — heroes, serpents and the far southern sky.

Aquila, Ara, Centaurus, Corona Australis, Corvus, Crater, Crux, Cygnus, Hercules, Hydra, Lupus, Lyra, Ophiuchus, Sagitta, Scutum, Serpens, Sextans, Triangulum Australe, Vulpecula.

The Orion family (5 constellations)

The Hunter and the animals around him, the brightest patch of sky.

Canis Major, Canis Minor, Lepus, Monoceros, Orion.

The Heavenly Waters family (9 constellations)

Constellations tied to water, ships and the sea.

Carina, Columba, Delphinus, Equuleus, Eridanus, Piscis Austrinus, Puppis, Pyxis, Vela.

The Bayer family (11 constellations)

Southern constellations charted by Dutch navigators in the 1590s.

Apus, Chamaeleon, Dorado, Grus, Hydrus, Indus, Musca, Pavo, Phoenix, Tucana, Volans.

The La Caille family (13 constellations)

Eighteenth-century southern constellations named after instruments.

Antlia, Caelum, Circinus, Fornax, Horologium, Mensa, Microscopium, Norma, Octans, Pictor, Reticulum, Sculptor, Telescopium.

All 88 constellations, A to Z

The largest is Hydra at 1303 square degrees; the smallest is Crux at 68. Every name links to a full guide.

Constellation	Abbr.	Meaning	Brightest star	Best seen	Family
Andromeda	And	Andromeda, the Chained Woman	Alpheratz (α And)	November	Perseus
Antlia	Ant	the Air Pump	α Ant	April	La Caille
Apus	Aps	The Bird-of-Paradise	α Aps (Paradys)	July	Bayer
Aquarius	Aqr	the Water-Bearer	β Aqr (Sadalsuud)	October	Zodiac
Aquila	Aql	the Eagle	Altair (α Aql)	August	Hercules
Ara	Ara	the Altar	β Ara	July	Hercules
Aries	Ari	the Ram	Hamal (α Ari)	December	Zodiac
Auriga	Aur	the Charioteer	Capella (α Aur)	February	Perseus
Boötes	Boo	The Herdsman	Arcturus (α Boo)	June	Ursa Major
Caelum	Cae	the chisel	α Cae	January	La Caille
Camelopardalis	Cam	Giraffe	β Cam	February	Ursa Major
Cancer	Cnc	the Crab	β Cnc (Tarf)	March	Zodiac
Canes Venatici	CVn	the Hunting Dogs	Cor Caroli (α CVn)	May	Ursa Major
Canis Major	CMa	the greater dog	Sirius (α CMa)	February	Orion
Canis Minor	CMi	The Lesser Dog	Procyon (α CMi)	February	Orion
Capricornus	Cap	the Sea-Goat	δ Cap (Deneb Algedi)	September	Zodiac
Carina	Car	the keel	Canopus (α Car)	March	Heavenly Waters
Cassiopeia	Cas	the Seated Queen	α Cas (Schedar)	November	Perseus
Centaurus	Cen	the Centaur	α Cen	May	Hercules
Cepheus	Cep	the King/King Cepheus	α Cep (Alderamin)	November	Perseus
Cetus	Cet	the Whale, Shark, or Sea Monster	Diphda	November	Perseus
Chamaeleon	Cha	the Chameleon	α Cha	April	Bayer
Circinus	Cir	Compass	α Cir (Xami)	June	La Caille
Columba	Col	the dove	α Col (Phact)	January	Heavenly Waters
Coma Berenices	Com	Berenice's hair	β Com	May	Ursa Major
Corona Australis	CrA	The Southern Crown	α CrA (Meridiana)	August	Hercules
Corona Borealis	CrB	The Northern Crown	α CrB (Alphecca or Gemma)	June	Ursa Major
Corvus	Crv	the Crow/Raven	γ Crv (Gienah)	May	Hercules
Crater	Crt	the cup	δ Crt	April	Hercules
Crux	Cru	Southern Cross	Acrux (α Cru)	May	Hercules
Cygnus	Cyg	the Swan or Northern Cross	Deneb (α Cyg)	September	Hercules
Delphinus	Del	dolphin	Rotanev (β Del)	September	Heavenly Waters
Dorado	Dor	the dolphinfish	α Dor	January	Bayer
Draco	Dra	the Dragon	γ Dra (Eltanin)	July	Ursa Major
Equuleus	Equ	the pony	α Equ (Kitalpha)	September	Heavenly Waters
Eridanus	Eri	the river Eridanus	Achernar (α Eri)	December	Heavenly Waters
Fornax	For	the brazier	α For	December	La Caille
Gemini	Gem	the Twins, Castor and Pollux	Pollux (β Gem)	February	Zodiac
Grus	Gru	the crane	α Gru (Alnair)	October	Bayer
Hercules	Her	Heracles	β Her (Kornephoros)	July	Hercules
Horologium	Hor	The Pendulum Clock	α Hor	December	La Caille
Hydra	Hya	the sea serpent	Alphard (α Hya)	April	Hercules
Hydrus	Hyi	the water snake	β Hyi	December	Bayer
Indus	Ind	the Indian	α Ind	September	Bayer
Lacerta	Lac	the Lizard	α Lac (Stellio)	October	Perseus
Leo	Leo	the Lion	Regulus (α Leo)	April	Zodiac
Leo Minor	LMi	the lesser Lion	Praecipua	April	Ursa Major
Lepus	Lep	the Hare	α Lep (Arneb)	January	Orion
Libra	Lib	the balance	β Lib	June	Zodiac
Lupus	Lup	The Wolf	α Lup (Uridim)	June	Hercules
Lynx	Lyn	the Lynx	α Lyn	February	Ursa Major
Lyra	Lyr	Lyre, harp	Vega (α Lyr)	August	Hercules
Mensa	Men	the Table Mountain	α Men (Hoerikwaggo)	January	La Caille
Microscopium	Mic	the Microscope	γ Mic	September	La Caille
Monoceros	Mon	the Unicorn	β Mon	February	Orion
Musca	Mus	the Fly	α Mus	May	Bayer
Norma	Nor	the carpenter's square	γ 2 Nor	June	La Caille
Octans	Oct	the Octant	ν Oct	October	La Caille
Ophiuchus	Oph	the serpent-bearer	α Oph (Rasalhague)	July	Hercules
Orion	Ori	Orion, the Hunter	Rigel (β Ori)	January	Orion
Pavo	Pav	the Peacock	α Pav (Peacock)	August	Bayer
Pegasus	Peg	the Winged Horse	ε Peg (Enif)	October	Perseus
Perseus	Per	Perseus	α Per (Mirfak)	December	Perseus
Phoenix	Phe	the Phoenix	α Phe (Ankaa)	November	Bayer
Pictor	Pic	Easel	α Pic	January	La Caille
Pisces	Psc	the Fishes	η Psc (Alpherg)	November	Zodiac
Piscis Austrinus	PsA	the Southern Fish	Fomalhaut (α PsA)	October	Heavenly Waters
Puppis	Pup	the Poop Deck	ζ Pup (Naos)	February	Heavenly Waters
Pyxis	Pyx	The compass box	α Pyx	March	Heavenly Waters
Reticulum	Ret	the Reticle	α Ret (Rhombus)	December	La Caille
Sagitta	Sge	the Arrow	γ Sge (Telum)	August	Hercules
Sagittarius	Sgr	the Archer	ε Sgr (Kaus Australis)	August	Zodiac
Scorpius	Sco	the Scorpion	Antares (α Sco)	July	Zodiac
Sculptor	Scl	the Sculptor	α Scl	November	La Caille
Scutum	Sct	the Shield of John III Sobieski	α Sct	August	Hercules
Serpens	Ser	the Snake	α Ser (Unukalhai)	July	Hercules
Sextans	Sex	the Sextant	α Sex	April	Hercules
Taurus	Tau	the Bull	Aldebaran (α Tau)	January	Zodiac
Telescopium	Tel	the Telescope	α Tel	August	La Caille
Triangulum	Tri	The Triangle	β Tri (Alaybasan)	December	Perseus
Triangulum Australe	TrA	the Southern Triangle	α TrA (Atria)	July	Hercules
Tucana	Tuc	the toucan	α Tuc (Lang-Exster)	October	Bayer
Ursa Major	UMa	the Great Bear	Alioth (ε UMa)	April	Ursa Major
Ursa Minor	UMi	the Little Bear	Polaris	June	Ursa Major
Vela	Vel	the Sails	γ Vel	March	Heavenly Waters
Virgo	Vir	the Maiden	Spica (α Vir)	May	Zodiac
Volans	Vol	the Flying Fish	γ 2 Vol	February	Bayer
Vulpecula	Vul	the Fox	α Vul (Anser)	September	Hercules

Actually going outside

You can do a great deal with nothing at all, and the jump from nothing to
binoculars is bigger than the jump from binoculars to a telescope.

With your eyes. Constellation patterns, the Milky Way, meteor showers, the
Andromeda Galaxy, the Magellanic Clouds, the Pleiades, bright double stars like
Mizar and Alcor. Give yourself twenty minutes away from any light for your
eyes to dark-adapt properly, and use red light if you need to see anything —
white light resets the process instantly.

With binoculars. This is the best value in astronomy. A cheap pair of 10x50s
transforms open clusters, shows the Orion Nebula as a glowing cloud, resolves the
Beehive and the Coathanger, and reveals hundreds of stars in the Milky Way. Some
objects — the Pleiades, the Hyades, the Coathanger — are actually worse
through a telescope, because they are larger than the field of view.

With a telescope. Planets, the Moon in detail, planetary nebulae, globular
clusters resolved into individual stars, galaxies. Aperture matters more than
magnification: a bigger mirror collects more light, and light is what you are
short of.

What actually limits you is not equipment but sky darkness and the Moon. A
full Moon washes out everything faint. Plan galaxy and nebula hunting around the
new Moon, and if you can drive thirty minutes away from a town, do — it will do
more for your view than any amount of money spent on gear.

Where to start

Eighty-eight regions, one sky, and a few thousand years of people looking at the
same stars and telling different stories about them. Pick a constellation you can
already find, read its write-up, and use its neighbours to reach the next one.

Every page below covers where to find it, what shape you are looking for, its
brightest stars, the story behind the name, what deep-sky objects are inside it,
and when and where you can actually see it — plus a summary table of every
observing fact worth knowing.