Your guide to the Solar System and the night sky
By donating now you help keep this site alive and free from ads. Please consider supporting this project.
🌎  Observing from: Greenwich, United Kingdom [change]
🌅 Sunrise: 6:34  ☀️ Transit: 13:02  🌅 Sunset: 19:31

τ Ceti (tau Ceti)

τ Ceti is a double main-sequence star in the constellation of Cetus.

τ Ceti visual magnitude is 3.5. Because of its moderate brightness, τ 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 τ Ceti:

τ Ceti (tau Ceti) is above the horizon from Greenwich, United Kingdom [change]. Altitude: 18°.

Celestial coordinates and finder chart of τ Ceti

τ 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 τ Ceti are provided in the following table:

01h 44m 04s
-15° 56’ 14”

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

Finder chart τ Ceti (tau Ceti) star
Simplified finder chart for τ Ceti (tau Ceti).

Visibility of τ Ceti from your location

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

Today's τ Ceti (tau Ceti) rise, transit and set times from Greenwich, United Kingdom [change] are the following (all times relative to the local timezone Europe/London):

Azimuth: 105.9°
Max altitude: 22.6°
Azimuth: 254.1°
τ Ceti (tau Ceti) is above the horizon from Greenwich, United Kingdom

Digitized Sky Survey image of τ Ceti

The image below is a photograph of τ 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 τ Ceti is -1.718 arcsec per year in Right Ascension and 0.856 arcsec per year in Declination and the associated displacement for the next 100 years is represented with the red arrow.

Image of τ Ceti (tau Ceti) star
DSS2 image of τ Ceti. The red arrow shows the motion of τ Ceti during the next 100 years (-2.86 arcmin in Right Ascension and 1.43 arcmin in declination);

Distance of τ Ceti from the Sun and relative movement

τ Ceti is distant 11.89 light years from the Sun and it is moving towards the Sun at the speed of 16 kilometers per second.

3.65 pc
11.89 ly
-16 km/s
-1.718 arcsec/year
0.856 arcsec/year

Spectral properties of τ Ceti

τ Ceti belongs to spectral class G8 and has a luminosity class of V corresponding to a main-sequence star.


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

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

τ Ceti star system properties

τ 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 τ Ceti double sysyem:

89.8 arcsec

Alternative designations of τ Ceti

τ Ceti
(tau Ceti)