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public LocationGreenwich, United Kingdom
TimezoneEurope/London
Sunrise: 4:42 
Transit: 12:59 
Sunset: 21:16
sunny   (Daytime)   What's Visible Now?

Alderamin - α Cephei (alpha Cephei)

Above the horizon.  Circumpolar today
Altitude: 33.8°   Azimuth: 330.9°   Direction: North-North-West

Alderamin, also designated as α Cephei (alpha Cephei), is a variable and multiple main-sequence star of spectral class A7 in the constellation of Cepheus.

Alderamin visual magnitude is 2.44, making it the 85th brightest star in the sky. Because of its brightness, Alderamin is clearly visible to the naked eye when observed from locations with dark skies, and should be also quite easily visible from light polluted areas.

Celestial coordinates and finder chart of Alderamin

Finder chart Alderamin - α Cephei (alpha Cephei) star
Simplified finder chart for Alderamin - α Cephei (alpha Cephei).

Alderamin is situated close to the northern celestial pole and, as such, it is visible for most part of the year from the northern hemisphere. Celestial coordinates for the J2000 equinox as well as galactic coordinates of Alderamin are provided in the following table:

21h 18m 34s
+62° 35’ 08”
101°
9.17°
Cepheus
Image of Alderamin - α Cephei (alpha Cephei) star
DSS2 image of Alderamin. The red arrow shows the motion of Alderamin during the next 1000 years (2.52 arcmin in Right Ascension and 0.82 arcmin in declination);

Key facts about Alderamin

2.44
Main-sequence

and has a luminosity class of V corresponding to a main-sequence star.

1.57
A7V
8011K

The red dot in the diagram below shows where Alderamin is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of Alderamin. Attribution: Richard Powell / CC BY-SA

Alderamin star system properties

Alderamin is a visual double star which can be observed only with the help of very large telescopes. The table below shows key information about the Alderamin double sysyem:

2.44
11.54
9.1
206.8 arcsec

Distance of Alderamin from the Sun and relative movement

Alderamin is distant 48.77 light years from the Sun and it is moving towards the Sun at the speed of 10 kilometers per second.

14.96 pc
48.77 ly
-10 km/s
0.151 arcsec/year
0.049 arcsec/year

Alternative designations of Alderamin

Alderamin
α Cephei
(alpha Cephei)
SAO19302
SAO19302

Visibility of Alderamin from your location

Alderamin - α Cephei (alpha Cephei) is circumpolar and transits at 03:38 UTC (altitude: 78.9°)