Your Guide to the Solar System and the Night Sky
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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 4:46  
clear_day Transit: 12:56  
SunsetSet: 21:07 south
wb_twilight Astronomical TwilightWhat's Visible Now
All Constellations » Coma Berenices » 

21 Comae Berenices

21 Comae Berenices is a variable star in the constellation of Coma Berenices.

21 Comae Berenices visual magnitude is 5.46. Because of its reltive faintness, 21 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 21 Comae Berenices:

5.46
21 Comae Berenices is above the horizon from Greenwich, United Kingdom edit_location_alt. Altitude: 22°.

Celestial coordinates and finder chart of 21 Comae Berenices

21 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 21 Comae Berenices are provided in the following table:

12h 31m 00s
+24° 34’ 01”
240.93°
84.74°
Coma Berenices

The simplified sky map below shows the position of 21 Comae Berenices in the sky:

Finder chart 21 Comae Berenices star
Simplified finder chart for 21 Comae Berenices.

Visibility of 21 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 21 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: 65.4°
Max altitude: 63.1°
Azimuth: 294.6°
21 Comae Berenices is above the horizon from Greenwich, United Kingdom

Digitized Sky Survey image of 21 Comae Berenices

The image below is a photograph of 21 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 21 Comae Berenices is -0.012 arcsec per year in Right Ascension and -0.009 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of 21 Comae Berenices star
DSS2 image of 21 Comae Berenices. The red arrow shows the motion of 21 Comae Berenices during the next 10000 years (-2.00 arcmin in Right Ascension and -1.50 arcmin in declination);

Distance of 21 Comae Berenices from the Sun and relative movement

21 Comae Berenices is distant 310.77 light years from the Sun

95.33 pc
310.77 ly
-0.012 arcsec/year
-0.009 arcsec/year

Spectral properties of 21 Comae Berenices

21 Comae Berenices belongs to spectral class A2

0.56
A2
9542K

The red dot in the diagram below shows where 21 Comae Berenices is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of 21 Comae Berenices. Attribution: Richard Powell / CC BY-SA

Alternative designations of 21 Comae Berenices

21 Comae Berenices
SAO82346
SAO82346