Contents
Cepheus Constellation: Stars, Mythology, Deep Space Objects & Facts
By : John Whitworth / Updated : Apr 15th, 2026 22:58
Contents
Cepheus Constellation Facts and Figures
- Name: Cepheus
- Meaning: King of Ethiopia
- Pronounciation : Cee-fee-us
- Abbrev. / Genitive : Cep / Cephei
- Creator : Ptolemy
- Zodiac Sign : No
- Area : 587.787 sq. deg. (1.42%)
- Celestial Hemisphere : North
- Neighbouring Constellations : Cassiopeia, Camelopardalis, Ursa Minor, Draco, Cygnus, Lacerta
- Largest Star : RW Cephei
- Brightest Star : Alderamin
Cepheus's Stars
Here are a few facts about the stars in the constellation.
- Cepheus has five stars that make up the constellation's shape.
- The Hipparcos satellite scanned and detailed one thousand eight hundred and eighty-five stars.
- You can see one hundred and seventy-eight stars within the Cepheus constellation borders with the naked eye on a clear night sky.
- Kruger 60 is Cepheus's nearest star, about 13.05 light-years from the Earth.
- The nearest star in Cepheus to the Earth with an exoplanet is HIP 109384, about 182.83 light-years away.
- RW Cephei is Cepheus's largest star in the constellation.
Alderamin
Cepheus's brightest star is Alderamin, about 49.05 light-years from the Sun. The star is recognised as the brightest in the constellation as it has the Bayer status of Alpha. Alderamin has an apparent magnitude of 2.45 but an absolute magnitude of 1.56. The difference between the magnitudes is that absolute magnitude is the object from 10 Parsecs or 32.6 light-years away from the observer, whereas apparent is from Earth.
Mu Cephei, Herschel's Garnet Star
It is referred to as Herschel's Garnet Star because it was seen as being red, very much like the mineral Garnet from which it gets its name. It is one of the largest stars known and the largest star that is currently visible to the naked eye. It is nearing death as it has begun converting helium into carbon. Stars can only undergo a limited number of conversions from one element to another before they explode. Wiki
RW Cephei
RW Cephei is an interesting star in the constellation, it is a humungous giant star. If it were in the centre, we would be within it. It is not the largest star in the night sky. The current largest is UY Scuti, which is 1,708 times as large, according to the latest research.
VV Cephei
In addition to the Cepheus constellation having RW Cephei, it also hosts VV Cephei, another supergiant star. This star is not as large as RW Cephei, but it is still an impressively large star and one which would encompass our star if it were in the centre of the solar system.
Other Major Stars
This is a list of other stars that make up part of the constellation but have been detailed above yet. Other visible stars in the constellation can be found Cepheus Star List page.
| Name | Bayer | Spectral Type | Distance | Exoplanets |
| Alfirk | Beta Cephei | B2IIIv SB | 685.22 | |
| Errai | Gamma Cephei | K1IV | 46.00 | Yes |
| Zeta Cephei | Zeta Cephei | K1Ibv SB | 836.32 | |
| Iota Cephei | Iota Cephei | K0III | 115.29 |
Quick Facts
- The Cepheus constellation contains the prototype for Cepheid Variables, a class of variable stars. The prototype is Alrediph, also known as Delta Cephei.
- It is a northern circumpolar constellation, meaning it can always be seen in the northern hemisphere throughout the year.
How to Find Cepheus in the night sky
Northern Hemisphere
Cepheus is one of four constellations that can be seen all year round in the Northern Hemisphere. There is no best or worst time for it. The only factors that could affect your viewing are light and your location in the Northern Hemisphere. Because of the Pole Star and its being visible all year round, navigators used it centuries ago.
Southern Hemisphere
In Darwin, Australia, you can see the Cepheus constellation above the horizon in November at about 8-9 pm. Any other time or location more southerly, you will not be able to see.
Mythology
Cepheus was the king of Philistia ( Now Ethiopia ) whose wife Cassiopeia ordered their daughter Andromeda be sacrificed to the Cetus sea whale to please the Gods.
Cassiopeia would be rescued from Cetus by Perseus using the severed head of Medusa, the Gorgon woman who had snakes for hair and whoever she looked at could turn them to stone.
Zodiac
Cepheus is not a member of the Zodiac group of twelve constellations that appear when the Sun sets. The Zodiac constellations are the ones astrologers use to predict a person's future based on their birth date.
Cepheus Distance From Earth
You cannot just go to one location and arrive in the Cepheus constellation, and this is because it is made up of stars at different positions and distances. Of the main stars, the nearest star (Errai) in the constellation is at a distance of 46.00 light-years, and the furthest star is Zeta Cephei, at a distance of 836.32 light-years. The average distance to the major stars is 346.38 light years. Main stars refer to the stars that make up the constellation outline.
Because of the distances of objects, we see how they looked in the past. To know how far back we are looking, take the amount and remove the word "Light", and you will get an idea of how long ago they looked like that. By now, the object may look different.
Cepheus Constellation Facts
| Name | Cepheus |
| Abbreviation | Cep |
| Zodiac Sign | No |
| Area | 587.787 sq. deg. |
| Night Sky | 1.42% |
| Size Position | 27th |
| Celestial Hemisphere | North |
| Meteor Shower(s) | 5 |
| Nearest Star | Kruger 60 |
| ...with Exoplanet(s) | HIP 109384 |
| Largest Star | RW Cephei |
| Brightest Star | Alderamin |
| Dimmest Star | HD 202987 |
| Furthest Star | HIP 104589 |
| Bright Star Count | 178 |
| Hipp. Star Count | 1885 |
| Main Star Count | 5 |
| Messier D.S.O. Count | 0 |
| Lists | Deep Space Objects |
| Exoplanets | |
| Meteor Showers | |
| Stars | |
| Main Stars | Alderamin |
| Alfirk | |
| Errai | |
| Zeta Cephei | |
| Iota Cephei |
