What it looks like
Andromeda is a large northern constellation drawn as a princess chained to a rock, awaiting rescue by Perseus. Its stars form a long chain stretching from the Great Square of Pegasus, and it contains M31, the Andromeda Galaxy — the most distant object visible to the naked eye.
Brightest stars
Andromeda's brightest stars are Alpheratz, shared with the Great Square of Pegasus, and Almach, a celebrated colourful double.
| Star | Magnitude | Distance | Meaning |
|---|---|---|---|
| Alpheratz (α Andromedae) | +2.06 | 97 ly | Navel of the Horse |
| Mirach (β Andromedae) | +2.06 | 197 ly | Girdle |
| Almach (γ Andromedae) | +2.10 | 390 ly | — |
| Delta Andromedae | +3.27 | 105 ly | — |
Mythology and history
In Greek myth, Andromeda was a princess chained to a rock as a sacrifice to a sea monster, rescued by Perseus who married her.
The chained princess
Andromeda was the daughter of Queen Cassiopeia and King Cepheus of Aethiopia. When Cassiopeia boasted that she was more beautiful than the Nereids, Poseidon sent the sea monster Cetus to ravage the coast. An oracle declared that only the sacrifice of Andromeda could appease the god, so she was chained to a rock by the sea. Perseus, flying past on his winged sandals, saw her, killed the monster, and married her. All the figures — Cassiopeia, Cepheus, Andromeda, Perseus and Cetus — are placed together in the sky.
How to find it
Follow the chain of stars from the northeast corner of the Great Square of Pegasus on autumn evenings.
- Find the Great Square of Pegasus first; Alpheratz is its northeast corner.
- Look for the faint smudge of M31 above Mirach.
- Best on autumn evenings from the northern hemisphere.
Key facts
- Abbreviation
- And
- Genitive
- Andromedae
- Meaning
- The Chained Princess
- Brightest star
- Alpheratz
- Main stars
- 7
- Area rank
- 19th
- Best visible
- November
- Declination
- +40°
- Meteor showers
- Andromedids
- Neighbours
- Perseus, Cassiopeia, Lacerta, Pegasus, Pisces, Triangulum
Deep-sky objects
The Andromeda Galaxy (M31) is the nearest large spiral galaxy, about 2.5 million light-years away and visible to the naked eye under dark skies. Its companions M32 and M110 sit alongside it, and the constellation also contains NGC 752, a bright open cluster.
Frequently asked questions
What does the constellation Andromeda look like?
Andromeda is a northern constellation known as the Chained Princess, home to the Andromeda Galaxy (M31), the nearest large galaxy to the Milky Way.
What is the brightest star in Andromeda?
The brightest star in Andromeda is Alpheratz, shining at around magnitude 2.06.
When is Andromeda best visible?
Andromeda is best seen from northern hemisphere during November.
What is the story behind Andromeda?
In Greek myth, Andromeda was a princess chained to a rock as a sacrifice to a sea monster, rescued by Perseus who married her.
Which constellations are near Andromeda?
Andromeda borders Perseus, Cassiopeia, Lacerta, Pegasus, Pisces and Triangulum.
Perseus
Pegasus