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

τ Sagittarii (tau Sagittarii)

τ Sagittarii is a giant star in the constellation of Sagittarius.

τ Sagittarii visual magnitude is 3.32. Because of its moderate brightness, τ Sagittarii 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 Sagittarii:

3.32
Giant
τ Sagittarii (tau Sagittarii) is below the horizon from Greenwich, United Kingdom [change].

Celestial coordinates and finder chart of τ Sagittarii

τ Sagittarii 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 Sagittarii are provided in the following table:

19h 06m 56s
-27° 40’ 14”
9.34°
-15.37°
Sagittarius

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

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

Visibility of τ Sagittarii from your location

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

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

Azimuth: 117.7°
Max altitude: 10.8°
Azimuth: 242.3°
τ Sagittarii (tau Sagittarii) is below the horizon from Greenwich, United Kingdom

Digitized Sky Survey image of τ Sagittarii

The image below is a photograph of τ Sagittarii 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 Sagittarii is -0.053 arcsec per year in Right Ascension and -0.251 arcsec per year in Declination and the associated displacement for the next 1000 years is represented with the red arrow.

Image of τ Sagittarii (tau Sagittarii) star
DSS2 image of τ Sagittarii. The red arrow shows the motion of τ Sagittarii during the next 1000 years (-0.88 arcmin in Right Ascension and -4.18 arcmin in declination);

Distance of τ Sagittarii from the Sun and relative movement

τ Sagittarii is distant 120.34 light years from the Sun and it is moving far from the Sun at the speed of 45 kilometers per second.

36.91 pc
120.34 ly
45 km/s
-0.053 arcsec/year
-0.251 arcsec/year

Spectral properties of τ Sagittarii

τ Sagittarii belongs to spectral class K1 and has a luminosity class of III corresponding to a giant star.

0.48
K1III
4328K

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

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

Alternative designations of τ Sagittarii

τ Sagittarii
(tau Sagittarii)
40 Sagittarii
SAO187683
SAO187683