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

Alkaphrah - κ Ursae Majoris (kappa Ursae Majoris)

Alkaphrah, also designated as κ Ursae Majoris (kappa Ursae Majoris), is a variable and double main-sequence star in the constellation of Ursa Major.

Alkaphrah visual magnitude is 3.6. Because of its moderate brightness, Alkaphrah 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 Alkaphrah:

3.6
Main-sequence
Alkaphrah - κ Ursae Majoris (kappa Ursae Majoris) is above the horizon from Greenwich, United Kingdom [change]. Altitude: 13°.

Celestial coordinates and finder chart of Alkaphrah

Alkaphrah is situated north of the celestial equator, as such, it is more easily visible from the northern hemisphere. Celestial coordinates for the J2000 equinox as well as galactic coordinates of Alkaphrah are provided in the following table:

09h 03m 37s
+47° 09’ 24”
172.63°
41.63°
Ursa Major

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

Finder chart Alkaphrah - κ Ursae Majoris (kappa Ursae Majoris) star
Simplified finder chart for Alkaphrah - κ Ursae Majoris (kappa Ursae Majoris).

Visibility of Alkaphrah from your location

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

Alkaphrah - κ Ursae Majoris (kappa Ursae Majoris) is circumpolar and transits at 06:39 UTC (altitude: 85.7°)

Digitized Sky Survey image of Alkaphrah

The image below is a photograph of Alkaphrah 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 Alkaphrah is -0.033 arcsec per year in Right Ascension and -0.054 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of Alkaphrah - κ Ursae Majoris (kappa Ursae Majoris) star
DSS2 image of Alkaphrah. The red arrow shows the motion of Alkaphrah during the next 10000 years (-5.50 arcmin in Right Ascension and -9.00 arcmin in declination);

Distance of Alkaphrah from the Sun and relative movement

Alkaphrah is distant 422.83 light years from the Sun and it is moving far from the Sun at the speed of 4 kilometers per second.

129.70 pc
422.83 ly
4 km/s
-0.033 arcsec/year
-0.054 arcsec/year

Spectral properties of Alkaphrah

Alkaphrah belongs to spectral class A1 and has a luminosity class of V corresponding to a main-sequence star.

-1.96
A1V
10125K

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

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

Alkaphrah star system properties

Alkaphrah 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 Alkaphrah double sysyem:

3.6
3.8
0.2
0.3 arcsec

Alternative designations of Alkaphrah

Alkaphrah
κ Ursae Majoris
(kappa Ursae Majoris)
12 Ursae Majoris
SAO42661
SAO42661