Your guide to the Solar System and the night sky
🌎 Location: Greenwich, United Kingdom [change]

τ Librae (tau Librae)

τ Librae is a main-sequence star in the constellation of Libra.

τ Librae visual magnitude is 3.66. Because of its moderate brightness, τ Librae 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 Librae:

τ Librae (tau Librae) is above the horizon from Greenwich, United Kingdom [change]. Altitude: 7°.

Celestial coordinates and finder chart of τ Librae

τ Librae is situated south of the celestial equator, as such, it is more easily visible from the southern emisphere. Celestial coordinates for the J2000 equinox as well as galactic coordinates of τ Librae are provided in the following table:

15h 38m 39s
-29° 46’ 40”

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

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

Visibility of τ Librae from your location

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

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

Azimuth: 119.8°
Max altitude: 8.7°
Azimuth: 240.2°
τ Librae (tau Librae) is above the horizon from Greenwich, United Kingdom

Digitized Sky Survey image of τ Librae

The image below is a photograph of τ Librae 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 Librae is -0.015 arcsec per year in Right Ascension and -0.03 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of τ Librae (tau Librae) star
DSS2 image of τ Librae. The red arrow shows the motion of τ Librae during the next 10000 years (-2.50 arcmin in Right Ascension and -5.00 arcmin in declination);

Distance of τ Librae from the Sun and relative movement

τ Librae is distant 444.75 light years from the Sun and it is moving far from the Sun at the speed of 3 kilometers per second.

136.43 pc
444.75 ly
3 km/s
-0.015 arcsec/year
-0.03 arcsec/year

Spectral properties of τ Librae

τ Librae belongs to spectral class B2 and has a luminosity class of V corresponding to a main-sequence star.


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

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

Alternative designations of τ Librae

τ Librae
(tau Librae)