We use cookies to deliver essential features and to measure their performance. By using this site you accept our Privacy Policies.
Help keep this site free and ads-free: donate now!
public LocationGreenwich, United Kingdom
Sunrise: 4:42 
Transit: 13:00 
Sunset: 21:17
sunny   (Daytime)   What's Visible Now?

τ1 Serpentis (tau1 Serpentis)

Below the horizon.  Rise: 15:12 | Tran: 22:31 | Set: 5:54
Altitude: -0.3°   Azimuth: 295.8°   Direction: West-North-West

τ1 Serpentis is a variable giant star of spectral class M1 in the constellation of Serpens.

τ1 Serpentis visual magnitude is 5.17. Because of its faintness, τ1 Serpentis 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 τ1 Serpentis

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

τ1 Serpentis 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 Serpentis are provided in the following table:

15h 25m 47s
+15° 25’ 41”
Image of τ1 Serpentis (tau1 Serpentis) star
DSS2 image of τ1 Serpentis. The red arrow shows the motion of τ1 Serpentis during the next 10000 years (-2.17 arcmin in Right Ascension and -1.17 arcmin in declination);

Key facts about τ1 Serpentis


and has a luminosity class of III corresponding to a giant star.


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

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

Distance of τ1 Serpentis from the Sun and relative movement

τ1 Serpentis is distant 918.31 light years from the Sun and it is moving towards the Sun at the speed of 20 kilometers per second.

281.69 pc
918.31 ly
-20 km/s
-0.013 arcsec/year
-0.007 arcsec/year

Alternative designations of τ1 Serpentis

τ1 Serpentis
(tau1 Serpentis)
9 Serpentis

Visibility of τ1 Serpentis from your location

Today's τ1 Serpentis (tau1 Serpentis) rise, transit and set times from Greenwich, United Kingdom are the following (all times relative to the local timezone Europe/London):

Azimuth: 74.6°
Max altitude: 53.9°
Azimuth: 285.4°