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: 6:59  
clear_day Transit: 12:48  
SunsetSet: 18:36 south
sunny DaytimeWhat's Visible Now
All Constellations » Cetus » 

θ Ceti (theta Ceti)

Altitude: -26.1°   Azimuth: 291.2°   Direction: West-North-West

θ Ceti is a double hypergiant star in the constellation of Cetus.

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


θ Ceti (theta Ceti) is below the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: -26.1°
Azimuth: 291.2°
Direction: West-North-West

Celestial coordinates and finder chart of θ Ceti

θ Ceti 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 θ Ceti are provided in the following table:

01h 24m 01s
-08° 10’ 59”

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

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

Visibility of θ Ceti 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 θ Ceti (theta Ceti) 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: 98.2°
Max altitude: 30.3°
Azimuth: 261.8°

Digitized Sky Survey image of θ Ceti

The image below is a photograph of θ Ceti 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 Ceti is -0.079 arcsec per year in Right Ascension and -0.218 arcsec per year in Declination and the associated displacement for the next 1000 years is represented with the red arrow.

Image of θ Ceti (theta Ceti) star
DSS2 image of θ Ceti. The red arrow shows the motion of θ Ceti during the next 1000 years (-1.32 arcmin in Right Ascension and -3.63 arcmin in declination);

Distance of θ Ceti from the Sun and relative movement

θ Ceti is distant 114.47 light years from the Sun and it is moving far from the Sun at the speed of 17 kilometers per second.

35.11 pc
114.47 ly
17 km/s
-0.079 arcsec/year
-0.218 arcsec/year

Spectral properties of θ Ceti

θ Ceti belongs to spectral class K0 and has a luminosity class of III corresponding to a hypergiant star.


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

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

θ Ceti star system properties

θ Ceti 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 θ Ceti double sysyem:

65.4 arcsec

Alternative designations of θ Ceti

θ Ceti
(theta Ceti)