τ Boötis (tau Boötis)
τ Boötis is a variable and double sub-giant star in the constellation of Boötes.
τ Boötis visual magnitude is 4.5. Because of its moderate brightness, τ Boötis should be easily visible from locations with dark skies, while it can be barely visible, or not visible at all, from skies affected by light pollution.
The proper motion of τ Boötis is -0.482 arcsec per year in Right Ascension and 0.041 arcsec per year in Declination and the associated displacement for the next 1000 years is represented with the red arrow.
Key facts about τ Boötis
τ Boötis (tau Boötis) is above the horizon from Greenwich, United Kingdom.
Altitude: 54.7°
Azimuth: 199.7°
Direction: South-South-West
Celestial coordinates and finder chart of τ Boötis
τ Boötis 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 Boötis are provided in the following table:
The simplified sky map below shows the position of τ Boötis in the sky:
Visibility of τ Boötis from your location
Location: Greenwich, United Kingdom
Latitude: 51° 28’ 47” N
Longitude: 0° 00’ 00” E
Timezone: Europe/London
Today's τ Boötis (tau Boötis) rise, transit and set times from Greenwich, United Kingdom are the following (all times relative to the local timezone Europe/London):
Distance of τ Boötis from the Sun and relative movement
τ Boötis is distant 50.84 light years from the Sun and it is moving towards the Sun at the speed of 16 kilometers per second.
Spectral properties of τ Boötis
τ Boötis belongs to spectral class F6 and has a luminosity class of IV corresponding to a sub-giant star.
The red dot in the diagram below shows where τ Boötis is situated in the Hertzsprung–Russell diagram.
τ Boötis star system properties
τ Boötis is a visual double star which can be observed only with the help of very large telescopes. The table below shows key information about the τ Boötis double sysyem: