Look up at a clear night sky and the stars appear scattered across the darkness. For thousands of years, however, people have connected them into recognizable patterns, imagining hunters, animals, heroes and mythical creatures stretched across the heavens. Today, astronomers recognize 88 constellations, preserving many of these ancient patterns alongside more recent additions.
Explore all 88 constellations ↓ | New to constellations? Start here ↓
What Is a Constellation?
We usually think of a constellation as a recognizable pattern of stars, but in modern astronomy it means something more precise. Each constellation occupies a defined region of the sky, containing every star, nebula and galaxy within its boundaries, whether or not they form part of a familiar pattern. Even the imaginary lines commonly drawn between stars aren’t official and can vary between star charts. The stars themselves may lie at vastly different distances, appearing grouped together only from our viewpoint on Earth.
Some familiar star patterns aren’t constellations at all. The Big Dipper, for example, is part of the much larger constellation Ursa Major. Such patterns are called asterisms: recognizable groups of stars that aren’t themselves official constellations.
Why Are There 88 Constellations?
The number has historical roots. Around the second century AD, the Greek astronomer Claudius Ptolemy cataloged 48 constellations, mostly visible from the Mediterranean. More constellations were introduced as European explorers and astronomers mapped previously uncharted parts of the southern sky, and boundaries remained inconsistent. In 1922, the International Astronomical Union (IAU) adopted the modern list of 88 constellations. Their official boundaries were established by 1930, dividing the entire sky into distinct regions without gaps.
Explore All 88 Constellations
| Andromeda Chained Maiden | Lacerta Lizard |
| Antlia Air Pump | Leo Lion |
| Apus Bird of Paradise | Leo Minor Lesser Lion |
| Aquarius Water Bearer | Lepus Hare |
| Aquila Eagle | Libra Scales |
| Ara Altar | Lupus Wolf |
| Aries Ram | Lynx Lynx |
| Auriga Charioteer | Lyra Lyre |
| Boötes Herdsman | Mensa Table Mountain |
| Caelum Engraving Tool | Microscopium Microscope |
| Camelopardalis Giraffe | Monoceros Unicorn |
| Cancer Crab | Musca Fly |
| Canes Venatici Hunting Dogs | Norma Carpenter’s Square |
| Canis Major Great Dog | Octans Octant |
| Canis Minor Lesser Dog | Ophiuchus Serpent Bearer |
| Capricornus Sea Goat | Orion Hunter |
| Carina Keel | Pavo Peacock |
| Cassiopeia Seated Queen | Pegasus Winged Horse |
| Centaurus Centaur | Perseus Hero |
| Cepheus King | Phoenix Phoenix |
| Cetus Sea Monster | Pictor Painter’s Easel |
| Chamaeleon Chameleon | Pisces Fishes |
| Circinus Drawing Compass | Piscis Austrinus Southern Fish |
| Columba Dove | Puppis Stern |
| Coma Berenices Berenice’s Hair | Pyxis Mariner Compass |
| Corona Australis Southern Crown | Reticulum Reticle |
| Corona Borealis Northern Crown | Sagitta Arrow |
| Corvus Crow | Sagittarius Archer |
| Crater Cup | Scorpius Scorpion |
| Crux Southern Cross | Sculptor Sculptor |
| Cygnus Swan | Scutum Shield |
| Delphinus Dolphin | Serpens Serpent |
| Dorado Swordfish | Sextans Sextant |
| Draco Dragon | Taurus Bull |
| Equuleus Little Horse | Telescopium Telescope |
| Eridanus River | Triangulum Triangle |
| Fornax Furnace | Triangulum Australe Southern Triangle |
| Gemini Twins | Tucana Toucan |
| Grus Crane | Ursa Major Great Bear |
| Hercules Hercules | Ursa Minor Little Bear |
| Horologium Clock | Vela Sails |
| Hydra Female Water Snake | Virgo Maiden |
| Hydrus Male Water Snake | Volans Flying Fish |
| Indus Indian | Vulpecula Fox |
New to Constellations? Start Here
Learning all 88 constellations might seem daunting, but there’s no need to memorize them at once. Start by recognizing a few obvious shapes, then use them as landmarks to find your way around the surrounding sky.
Start With an Easy Pattern
For Northern Hemisphere observers, Orion is one of the easiest constellations to learn. It’s large, bright and distinctive, with four prominent stars forming a rough rectangle around the unmistakable line of three stars in Orion’s Belt. Once you recognize this shape, you can use Orion to map the surrounding night sky, with the Belt providing a useful signpost to other parts of the winter sky.
Extend the line of Orion’s Belt southeast and it leads toward Sirius, the brightest star in the night sky, in the constellation Canis Major. Extend it northwest and it points roughly toward Aldebaran, a bright reddish star in the constellation Taurus.
Another useful northern landmark is Ursa Major, a large constellation containing the seven bright stars that form the familiar Big Dipper asterism, which can also be used to find Polaris, the North Star.
In the Southern Hemisphere, Crux, the Southern Cross, provides a similarly distinctive starting point. Its compact cross shape is easy to recognize, while two nearby bright stars, Alpha and Beta Centauri, point toward it and can help you locate it.
The important thing isn’t which constellation you learn first. It’s the method: find one reliable landmark, learn what surrounds it, and gradually expand outward.
Learn What’s Visible From Where You Live
You won’t be able to see all 88 constellations from one location, and the sky doesn’t stay the same throughout the year. What you can see depends mainly on your latitude, the season and the time of night.
Some constellations lie so far north or south that they never rise from certain parts of Earth, while others can be seen from large portions of both hemispheres. The constellations visible also change throughout the year. As Earth orbits the Sun, the nighttime side of our planet gradually faces different parts of space, bringing different constellations into view. Six months later, Earth is on the opposite side of its orbit and the nighttime sky faces roughly the opposite direction.
This is why Orion is a familiar sight on winter evenings in the Northern Hemisphere but appears during summer in the Southern Hemisphere. Some constellations are also circumpolar from particular latitudes, meaning they remain above the horizon throughout the year.
Use Mythology to Remember Constellations
Constellations don’t have to be learned as 88 unrelated names. Some occupy neighboring parts of the sky and are connected by the same traditional stories.
Perseus, Andromeda, Cassiopeia, Cepheus, Pegasus and Cetus, for example, appear in the same broad region of the sky and are connected through Greek mythology. Perseus rescues Andromeda, whose parents are Cassiopeia and Cepheus, from the sea monster Cetus, while Pegasus is the winged horse associated with Perseus. Learning these stories gives you a memorable way to connect neighboring constellations rather than learning six unrelated names.
Once you recognize one constellation, learning its neighbors gradually turns that part of the sky into familiar territory. What first looked like a scattering of stars becomes a map of recognizable landmarks.
Explore More Constellation Guides
Once you’ve started recognizing the constellations, there are several ways to explore them in more depth.
- Seasonal Constellations: For Northern Hemisphere observers, our winter, spring, summer and autumn constellation guides highlight some of the most recognizable patterns visible during each season.
- Zodiac Constellations: Our guide to the 12 zodiac constellations explores their order along the ecliptic, their principal stars and why the Sun’s annual path through the sky actually carries it through a 13th constellation, Ophiuchus.
- Seasonal Asterisms: Familiar star patterns such as the Big Dipper, Summer Triangle, Northern Cross and Teapot provide useful signposts for navigating the night sky.
- Constellation Facts: Which constellation is the largest or smallest? How do constellations appear to move across the sky, and how far back do some of their stories go? Our collection of constellation facts explores these questions alongside other records and historical details.