Skip to content
EntityQ13265· pop 29· linked from 156 articles

Gamma Cephei

Sign in to save

Also known as Alrai, Errai, 35 Cephei, 35 Cep, γ Cep, γ Cephei, GJ 903, GCRV 14826

star in the constellation of Cephei

Key facts

Constellation
Cepheus
Right ascension
23 39 20.910
Declination
+77 ° 37 ′ 56.51 ″
Evolutionary stage
Red-giant branch
Spectral type
K1III-IV CN1
U b color index
+0.94
B v color index
+1.03
Variable type
Suspected

via Wikipedia infobox

Wikidata facts

Constellation
Cepheus
Child body
Gamma Cephei Ab
Distance from Earth
13.79
Diameter
6860000
Radius
4.9
Mass
1.4
Image
Cepheus constellation map.png
Show 17 more facts
catalog code
UBV M 27166
spectral class
K0IV
topic's main category
Category:Gamma Cephei
radial velocity
-43.668
apparent magnitude
3.22
metallicity
0.15
parallax
72.5167
absolute magnitude
2.52
effective temperature
4800
epoch
J2000.0
stellar rotational velocity
5.0
surface gravity
2000
right ascension component of proper motion
-65
declination component of proper motion
154
age estimated by a dating method
6.6
right ascension
354.83712672241
declination
77.63236410594
Sources (1)

via Wikidata · CC0

~5 min read

Encyclopedic overview

Gamma Cephei is a binary star system in the northern constellation of Cepheus. Its name is a Bayer designation that is Latinized from γ Cephei, and abbreviated Gamma Cep or γ Cep. This system is visible to the naked eye as a point of light with a combined apparent visual magnitude of 3.21. Based on parallax measurements, it is located at a distance of approximately 45 light-years from Earth.

The primary, Gamma Cephei A, is officially named Errai, pronounced /ɛˈreɪ.iː/, the traditional name of the system. It is a stellar class K1 orange giant or subgiant star. The companion, Gamma Cephei B, is a low mass red dwarf star. A conformed exoplanet is orbiting the primary; it is designated Gamma Cephei Ab, later named Tadmor.

Excerpted from Wikipedia’s “Gamma Cephei” article, available under the CC BY-SA 4.0 licence.