δ Cephei (delta Cephei)

Above the horizon. Circumpolar today

Alt: 69.34° Az: 303.41° Direction: South

δ Cephei is a variable and multiple supergiant star of spectral class F5 in the constellation of Cepheus.

δ Cephei visual magnitude is 3.75. Because of its moderate brightness, δ Cephei is easily visible to the naked eye from locations with dark skies, while it might be barely visible, or not visible at all, from light-polluted skies.

DSS2 image of δ Cephei. The red arrow shows the motion of δ Cephei during the next 10000 years (2.50 arcmin in Right Ascension and 0.17 arcmin in declination);

Celestial Coordinates

Apparent

Right Ascension 22h 30m 07s

Declination +58° 32’ 46”

Hour Angle 02h 17m 25s

Sidereal Time 00h 47m 32s

J2000

Right Ascension 22h 29m 10s

Declination +58° 24’ 55”

Galactic Coordinates

Galactic Longitude 105.19°

Galactic Latitude 0.53°

Finder Chart

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Finder chart for δ Cephei (delta Cephei).

Magnitude, Color, Spectral Class

Color ⬤

Magnitude 3.75

Class Supergiant

Absolute magnitude -3.64

Spectral Type F5I

Color Index (B-V) 0.6

Temperature 5968K

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

H-R diagram showing the position of δ Cephei. Attribution: Richard Powell / CC BY-SA

Star System Properties

δ Cephei is a visual double star which can be observed with binoculars or small telescopes. The table below shows key information about the δ Cephei double sysyem:

Main star magnitude 3.75

Secondary star magnitude 6.15

Magnitude difference 2.4

Separation 40.8 arcsec

Distance, Radial Speed, Proper Motion

δ Cephei is distant 981.93 light years from the Sun and it is moving towards the Sun at the speed of 15 kilometers per second.

Distance (parsec) 301.20

Distance (light year) 981.93

Radial Speed -15 km/s

Proper Motion RA 0.015 arcsec/y

Proper Motion Dec 0.001"/y

Alternative Designations

Bayer designation δ Cephei
(delta Cephei)

Flamsteed designation 27 Cephei

Henry Draper Catalogue HD213306

SAO Catalogue SAO34508

Hipparcos Catalogue HIP110991

Durchmusterung Catalogue BD+57 2548

FK5 Catalogue 847

General Catalogue of Variable Stars Del Cep

Aitken Double Star Catalogue ADS15987

Visibility from Your Location

δ Cephei (delta Cephei) is circumpolar and transits at 04:15 UTC (altitude: 82.9°)

Set Location

Other stars in Cepheus