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public LocationGreenwich, United Kingdom
TimezoneEurope/London
Sunrise: 4:42 
Transit: 12:59 
Sunset: 21:16
sunny   (Daytime)   What's Visible Now?

τ Ophiuchi (tau Ophiuchi)

Below the horizon.  Rise: 20:07 | Tran: 1:27 | Set: 6:44
Altitude: -10.7°   Azimuth: 89.8°   Direction: East

τ Ophiuchi is a variable and multiple main-sequence star of spectral class F2 in the constellation of Ophiuchus.

τ Ophiuchi visual magnitude is 5.24. Because of its faintness, τ Ophiuchi is visible to the naked eye only from locations with very dark skies, while it is not visible at all from skies affected by light pollution.

Celestial coordinates and finder chart of τ Ophiuchi

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

τ Ophiuchi 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 Ophiuchi are provided in the following table:

18h 03m 04s
-08° 10’ 50”
20.06°
6.87°
Ophiuchus
Image of τ Ophiuchi (tau Ophiuchi) star
DSS2 image of τ Ophiuchi. The red arrow shows the motion of τ Ophiuchi during the next 10000 years (4.67 arcmin in Right Ascension and -6.17 arcmin in declination);

Key facts about τ Ophiuchi

5.24
Main-sequence

and has a luminosity class of V corresponding to a main-sequence star.

1.66
F2V
6989K

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

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

τ Ophiuchi star system properties

τ Ophiuchi is a visual double star which can be observed with the help of medium or large telescopes. The table below shows key information about the τ Ophiuchi double sysyem:

5.24
5.94
0.7
1.9 arcsec

Distance of τ Ophiuchi from the Sun and relative movement

τ Ophiuchi is distant 169.61 light years from the Sun and it is moving towards the Sun at the speed of 40 kilometers per second.

52.03 pc
169.61 ly
-40 km/s
0.028 arcsec/year
-0.037 arcsec/year

Alternative designations of τ Ophiuchi

τ Ophiuchi
(tau Ophiuchi)
69 Ophiuchi
SAO142050
SAO142050
Gl 700.1A

Visibility of τ Ophiuchi from your location

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

Azimuth: 98.2°
Max altitude: 30.3°
Azimuth: 261.8°