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:

Color of τ Ceti ⬤

Magnitude of τ Ceti 3.5

Class Main-sequence

VISIBILITY RIGHT NOW 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:

Right Ascension J2000 01h 44m 04s

Declination J2000 -15° 56’ 14”

Galactic Longitude 173.19°

Galactic Latitude -73.43°

Constellation Cetus

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

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° RISE 9:27

Max altitude: 22.6° TRANSIT 14:01

Azimuth: 254.1° SET 18:35

RIGHT NOW 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.

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.

Distance (parsec) 3.65 pc

Distance (light year) 11.89 ly

Heliocentric radial velocity -16 km/s

Proper Motion RA -1.718 arcsec/year

Proper Motion Dec 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.

Absolute magnitude 5.69

Spectral Type G8V

Color Index (B-V) 0.72

Temperature of τ Ceti 5534K

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

Main star magnitude 3.5

Secondary star magnitude 13

Magnitude difference 9.5

Separation 89.8 arcsec

Alternative designations of τ Ceti

Bayer designation τ Ceti
(tau Ceti)

Flamsteed designation 52 Ceti

Henry Draper Catalogue HD10700

SAO Catalogue SAO147986

Hipparcos Catalogue HIP8102

Durchmusterung Catalogue BD-16 295

Gliese Catalogue Gl 71

FK5 Catalogue 59

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Other stars in Cetus