Your guide to the Solar System and the night sky
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🌎  Observing from: Greenwich, United Kingdom [change]
🌅 Sunrise: 6:45  ☀️ Transit: 13:03  🌅 Sunset: 19:23

θ Cassiopeiae (theta Cassiopeiae)

θ Cassiopeiae is a variable and double main-sequence star in the constellation of Cassiopeia.

θ Cassiopeiae visual magnitude is 4.33. Because of its moderate brightness, θ 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 θ Cassiopeiae:

θ Cassiopeiae (theta Cassiopeiae) is above the horizon from Greenwich, United Kingdom [change]. Altitude: 26°.

Celestial coordinates and finder chart of θ Cassiopeiae

θ 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 θ Cassiopeiae are provided in the following table:

01h 11m 06s
+55° 08’ 58”

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

Finder chart θ Cassiopeiae (theta Cassiopeiae) star
Simplified finder chart for θ Cassiopeiae (theta Cassiopeiae).

Visibility of θ Cassiopeiae from your location

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

θ Cassiopeiae (theta Cassiopeiae) is circumpolar and transits at 12:48 UTC (altitude: 86.3°)

Digitized Sky Survey image of θ Cassiopeiae

The image below is a photograph of θ 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 θ Cassiopeiae is 0.229 arcsec per year in Right Ascension and -0.022 arcsec per year in Declination and the associated displacement for the next 1000 years is represented with the red arrow.

Image of θ Cassiopeiae (theta Cassiopeiae) star
DSS2 image of θ Cassiopeiae. The red arrow shows the motion of θ Cassiopeiae during the next 1000 years (3.82 arcmin in Right Ascension and -0.37 arcmin in declination);

Distance of θ Cassiopeiae from the Sun and relative movement

θ Cassiopeiae is distant 137.38 light years from the Sun and it is moving far from the Sun at the speed of 9 kilometers per second.

42.14 pc
137.38 ly
9 km/s
0.229 arcsec/year
-0.022 arcsec/year

Spectral properties of θ Cassiopeiae

θ Cassiopeiae belongs to spectral class A7 and has a luminosity class of V corresponding to a main-sequence star.


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

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

θ Cassiopeiae star system properties

θ Cassiopeiae is a visual double star which can be observed with the help of small or medium telescopes. The table below shows key information about the θ Cassiopeiae double sysyem:

145.6 arcsec

Alternative designations of θ Cassiopeiae

θ Cassiopeiae
(theta Cassiopeiae)
33 Cassiopeiae