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A Complete Guide to the Solar System and the Night Sky
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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 7:48  
clear_day Transit: 11:49  
SunsetSet: 15:50 south
sleep NighttimeWhat's Visible Now?
All Constellations » Coma Berenices » 

α Comae Berenices (alpha Comae Berenices)

Altitude: -21.0°   Azimuth: 2.3°   Direction: North

α Comae Berenices is a variable and multiple main-sequence star in the constellation of Coma Berenices.

α Comae Berenices visual magnitude is 5.22. Because of its reltive faintness, α Comae Berenices should be visible only from locations with dark skyes, while it is not visible at all from skyes affected by light pollution.

The table below summarizes the key facts about α Comae Berenices:

5.22
Main-sequence

α Comae Berenices (alpha Comae Berenices) is below the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: -21.0°
Azimuth: 2.3°
Direction: North

Celestial coordinates and finder chart of α Comae Berenices

α Comae Berenices is situated close to the celestial equator, as such, it is at least partly visible from both hemispheres in certain times of the year. Celestial coordinates for the J2000 equinox as well as galactic coordinates of α Comae Berenices are provided in the following table:

13h 09m 59s
+17° 31’ 45”
327.96°
79.49°
Coma Berenices

The simplified sky map below shows the position of α Comae Berenices in the sky:

Finder chart α Comae Berenices (alpha Comae Berenices) star
Simplified finder chart for α Comae Berenices (alpha Comae Berenices).

Visibility of α Comae Berenices from your location

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

Today's α Comae Berenices (alpha Comae Berenices) rise, transit and set times from Greenwich, United Kingdom edit_location_alt are the following (all times relative to the local timezone Europe/London):

Azimuth: 72.5°
Max altitude: 56.0°
Azimuth: 287.5°

Digitized Sky Survey image of α Comae Berenices

The image below is a photograph of α Comae Berenices 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 α Comae Berenices is -0.43 arcsec per year in Right Ascension and 0.136 arcsec per year in Declination and the associated displacement for the next 1000 years is represented with the red arrow.

Image of α Comae Berenices (alpha Comae Berenices) star
DSS2 image of α Comae Berenices. The red arrow shows the motion of α Comae Berenices during the next 1000 years (-7.17 arcmin in Right Ascension and 2.27 arcmin in declination);

Distance of α Comae Berenices from the Sun and relative movement

α Comae Berenices is distant 46.70 light years from the Sun and it is moving towards the Sun at the speed of 18 kilometers per second.

14.32 pc
46.70 ly
-18 km/s
-0.43 arcsec/year
0.136 arcsec/year

Spectral properties of α Comae Berenices

α Comae Berenices belongs to spectral class F5 and has a luminosity class of V corresponding to a main-sequence star.

4.44
F5V
10125K

The red dot in the diagram below shows where α Comae Berenices is situated in the Hertzsprung–Russell diagram.

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

α Comae Berenices star system properties

α Comae Berenices 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 α Comae Berenices double sysyem:

5.22
5.32
0.1
0.2 arcsec

Alternative designations of α Comae Berenices

α Comae Berenices
(alpha Comae Berenices)
42 Comae Berenices
SAO100443
SAO100443
Gl 501 B