Your guide to the Solar System and the night sky
🌎 Location: Greenwich, United Kingdom [change]

Errai - γ Cephei (gamma Cephei)

Errai, also designated as γ Cephei (gamma Cephei), is a variable giant star in the constellation of Cepheus.

Errai visual magnitude is 3.21. Because of its moderate brightness, Errai should be easily visible from locations with dark skyes, while it can be barely visible, or not visible at all, from skyes affected by light pollution.

The table below summarizes the key facts about Errai:

3.21
Giant
Errai - γ Cephei (gamma Cephei) is above the horizon from Greenwich, United Kingdom [change]. Altitude: 64°.

Celestial coordinates and finder chart of Errai

Errai 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 Errai are provided in the following table:

23h 39m 20s
+77° 37’ 56”
118.99°
15.31°
Cepheus

The simplified sky map below shows the position of Errai in the sky:

Finder chart Errai - γ Cephei (gamma Cephei) star
Simplified finder chart for Errai - γ Cephei (gamma Cephei).

Visibility of Errai from your location

Location: Greenwich, United Kingdom [change]
Latitude: 51° 28’ 47” N
Longitude: 0° 00’ 00” E
Timezone: Europe/London

Errai - γ Cephei (gamma Cephei) is circumpolar and transits at 21:32 UTC (altitude: 63.8°)

Digitized Sky Survey image of Errai

The image below is a photograph of Errai from the Digitized Sky Survey 2 (DSS2 - see the credits section) taken in the red channel. The area of sky represented in the image is 0.5x0.5 degrees (30x30 arcmins). The proper motion of Errai is -0.067 arcsec per year in Right Ascension and 0.151 arcsec per year in Declination and the associated displacement for the next 1000 years is represented with the red arrow.

Image of Errai - γ Cephei (gamma Cephei) star
DSS2 image of Errai. The red arrow shows the motion of Errai during the next 1000 years (-1.12 arcmin in Right Ascension and 2.52 arcmin in declination);

Distance of Errai from the Sun and relative movement

Errai is distant 44.97 light years from the Sun and it is moving towards the Sun at the speed of 42 kilometers per second.

13.79 pc
44.97 ly
-42 km/s
-0.067 arcsec/year
0.151 arcsec/year

Spectral properties of Errai

Errai belongs to spectral class K1 and has a luminosity class of III corresponding to a giant star.

2.51
K1III
4672K

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

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

Alternative designations of Errai

Errai
γ Cephei
(gamma Cephei)
SAO10818
SAO10818