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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 6:49  
clear_day Transit: 12:50  
SunsetSet: 18:50 south
wb_twilight Nautical TwilightWhat's Visible Now
All Constellations » Eridanus » 

τ1 Eridani (tau1 Eridani)

Altitude: -29.1°   Azimuth: 83.5°   Direction: East

τ1 Eridani is a main-sequence star in the constellation of Eridanus.

τ1 Eridani visual magnitude is 4.47. Because of its moderate brightness, τ1 Eridani 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 τ1 Eridani:


τ1 Eridani (tau1 Eridani) is below the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: -29.1°
Azimuth: 83.5°
Direction: East

Celestial coordinates and finder chart of τ1 Eridani

τ1 Eridani 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 τ1 Eridani are provided in the following table:

02h 45m 06s
-18° 34’ 21”

The simplified sky map below shows the position of τ1 Eridani in the sky:

Finder chart τ1 Eridani (tau1 Eridani) star
Simplified finder chart for τ1 Eridani (tau1 Eridani).

Visibility of τ1 Eridani 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 τ1 Eridani (tau1 Eridani) 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: 108.6°
Max altitude: 19.9°
Azimuth: 251.4°

Digitized Sky Survey image of τ1 Eridani

The image below is a photograph of τ1 Eridani 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 τ1 Eridani is 0.33 arcsec per year in Right Ascension and 0.038 arcsec per year in Declination and the associated displacement for the next 1000 years is represented with the red arrow.

Image of τ1 Eridani (tau1 Eridani) star
DSS2 image of τ1 Eridani. The red arrow shows the motion of τ1 Eridani during the next 1000 years (5.50 arcmin in Right Ascension and 0.63 arcmin in declination);

Distance of τ1 Eridani from the Sun and relative movement

τ1 Eridani is distant 45.56 light years from the Sun and it is moving far from the Sun at the speed of 26 kilometers per second.

13.97 pc
45.56 ly
26 km/s
0.33 arcsec/year
0.038 arcsec/year

Spectral properties of τ1 Eridani

τ1 Eridani belongs to spectral class F6 and has a luminosity class of V corresponding to a main-sequence star.


The red dot in the diagram below shows where τ1 Eridani is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of τ1 Eridani. Attribution: Richard Powell / CC BY-SA

Alternative designations of τ1 Eridani

τ1 Eridani
(tau1 Eridani)