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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 6:52  
clear_day Transit: 12:49  
SunsetSet: 18:46 south
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All Constellations » Cassiopeia » 

ο Cassiopeiae (omicron Cassiopeiae)

Altitude: 15.4°   Azimuth: 26.3°   Direction: North-North-East

ο Cassiopeiae is a variable and double giant star in the constellation of Cassiopeia.

ο Cassiopeiae visual magnitude is 4.54. Because of its moderate brightness, ο Cassiopeiae 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 ο Cassiopeiae:


ο Cassiopeiae (omicron Cassiopeiae) is above the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: 15.4°
Azimuth: 26.3°
Direction: North-North-East

Celestial coordinates and finder chart of ο Cassiopeiae

ο Cassiopeiae 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 ο Cassiopeiae are provided in the following table:

00h 44m 43s
+48° 17’ 03”

The simplified sky map below shows the position of ο Cassiopeiae in the sky:

Finder chart ο Cassiopeiae (omicron Cassiopeiae) star
Simplified finder chart for ο Cassiopeiae (omicron Cassiopeiae).

Visibility of ο Cassiopeiae from your location

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

ο Cassiopeiae (omicron Cassiopeiae) is circumpolar and transits at 00:22 UTC (altitude: 86.8°)

Digitized Sky Survey image of ο Cassiopeiae

The image below is a photograph of ο Cassiopeiae 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 ο Cassiopeiae is 0.019 arcsec per year in Right Ascension and -0.008 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of ο Cassiopeiae (omicron Cassiopeiae) star
DSS2 image of ο Cassiopeiae. The red arrow shows the motion of ο Cassiopeiae during the next 10000 years (3.17 arcmin in Right Ascension and -1.33 arcmin in declination);

Distance of ο Cassiopeiae from the Sun and relative movement

ο Cassiopeiae is distant 905.56 light years from the Sun and it is moving towards the Sun at the speed of 17 kilometers per second.

277.78 pc
905.56 ly
-17 km/s
0.019 arcsec/year
-0.008 arcsec/year

Spectral properties of ο Cassiopeiae

ο Cassiopeiae belongs to spectral class B5 and has a luminosity class of III corresponding to a giant star.


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

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

ο Cassiopeiae star system properties

ο Cassiopeiae 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 ο Cassiopeiae double sysyem:

33.6 arcsec

Alternative designations of ο Cassiopeiae

ο Cassiopeiae
(omicron Cassiopeiae)
22 Cassiopeiae