Chained Princess · pronounced Andromeda. Andromeda, meaning “Chained Princess,” is an official IAU constellation centred near right ascension 0.1 hours and declination 43°. Its observing character is defined by the named stars and targets below. Andromeda belongs to the Perseus myth cycle: the princess was chained as a sacrifice to Cetus and rescued by Perseus. Ptolemy catalogued the figure, while Alpheratz was once counted in both Andromeda and Pegasus. The line figure is only a guide: the IAU boundary is the scientifically meaningful region, while historical and cultural interpretations require their own context.
About Andromeda
Andromeda is one of the 88 constellations recognized by the International Astronomical Union. Its standard three-letter abbreviation is And, and astronomers use the genitive form Andromedae when naming stars associated with it. The constellation's reference position lies around right ascension 0.1 hours and declination +43 degrees.
Its location places it in the northern sky. For a typical mid-latitude observer, this part of the celestial sphere is especially well placed during autumn evenings. Exact visibility depends on latitude, local horizon, date and time.
History and mythology of Andromeda
Origins and cultural history
Andromeda belongs to the Perseus myth cycle: the princess was chained as a sacrifice to Cetus and rescued by Perseus. Ptolemy catalogued the figure, while Alpheratz was once counted in both Andromeda and Pegasus.
From figure to official region
The IAU retained Chained Princess as one of 88 official constellations in 1922; Eugène Delporte’s boundaries later turned the traditional figure into an exact cataloguing region.
How to find Andromeda
- Locate the Great Square of Pegasus.
- Begin at Alpheratz, its northeastern corner, then follow Delta Andromedae, Mirach and Almach eastward.
- From Mirach move north through Mu and Nu Andromedae; M31 appears as an elongated haze in a dark sky.
- Use binoculars first: M31 spans much more sky than a telescope’s high-power field.
Bright stars in Andromeda
Alpheratz
Notable star- Magnitude
- 2.06
- Distance
- 97 light-years
Blue-white binary shared historically with the Great Square of Pegasus.
Mirach
Notable star- Magnitude
- 2.05
- Distance
- about 197 light-years
Red giant marking Andromeda’s hip; Mirach’s Ghost lies nearby.
Almach
Notable star- Magnitude
- 2.10 combined
- Distance
- about 350 light-years
Colour-contrast multiple star, orange and blue through a small telescope.
Delta Andromedae
Notable star- Magnitude
- 3.27
- Distance
- about 105 light-years
Orange giant on the chain west of Mirach.
Deep-sky objects in Andromeda
Andromeda Galaxy (M31)
Nearest large spiral to the Milky Way and visible without optical aid under dark skies.
M32
Bright satellite projected close to M31’s nucleus.
M110
Diffuse companion of M31, easier in dark transparent conditions.
NGC 752
Large, loose binocular cluster near the Aries border.
Interesting facts about Andromeda
- Andromeda’s traditional name refers to chained princess, while its official IAU boundary defines a precise region of the sky.
- Alpheratz, at magnitude 2.06, is a key star in Andromeda. Blue-white binary shared historically with the Great Square of Pegasus.
- Andromeda Galaxy (M31) is a notable spiral galaxy in Andromeda. Nearest large spiral to the Milky Way and visible without optical aid under dark skies.
- M32, a compact elliptical galaxy, is another observing target within the constellation.
- Andromeda belongs to the Perseus myth cycle: the princess was chained as a sacrifice to Cetus and rescued by Perseus.