τ Geminorum (tau Geminorum)

Above the horizon. Rise: 7:01 | Tran: 16:06 | Set: 1:15

Alt: 55.81° Az: 114.32° Direction: East-South-East

τ Geminorum is a variable and multiple giant star of spectral class K2 in the constellation of Gemini.

τ Geminorum visual magnitude is 4.41. Because of its moderate brightness, τ Geminorum is easily visible to the naked eye from locations with dark skies, while it might be barely visible, or not visible at all, from light-polluted skies.

Image of τ Geminorum (tau Geminorum) star

DSS2 image of τ Geminorum. The red arrow shows the motion of τ Geminorum during the next 10000 years (-5.00 arcmin in Right Ascension and -7.50 arcmin in declination);

Celestial Coordinates

Apparent

Right Ascension 07h 12m 45s

Declination +30° 12’ 05”

Hour Angle 21h 34m 40s

Sidereal Time 04h 47m 25s

J2000

Right Ascension 07h 11m 08s

Declination +30° 14’ 43”

Galactic Coordinates

Galactic Longitude 187.22°

Galactic Latitude 17.2°

Finder Chart

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Finder chart for τ Geminorum (tau Geminorum).

Magnitude, Color, Spectral Class

Color ⬤

Magnitude 4.41

Class Giant

Absolute magnitude -0.42

Spectral Type K2III

Color Index (B-V) 1.26

Temperature 4194K

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

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

Star System Properties

τ Geminorum 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 Geminorum double sysyem:

Main star magnitude 4.41

Secondary star magnitude 10.91

Magnitude difference 6.5

Separation 1.9 arcsec

Distance, Radial Speed, Proper Motion

τ Geminorum is distant 301.57 light years from the Sun and it is moving far from the Sun at the speed of 22 kilometers per second.

Distance (parsec) 92.51

Distance (light year) 301.57

Radial Speed 22 km/s

Proper Motion RA -0.03 arcsec/y

Proper Motion Dec -0.045"/y

Alternative Designations

Bayer designation τ Geminorum
(tau Geminorum)

Flamsteed designation 46 Geminorum

Henry Draper Catalogue HD54719

SAO Catalogue SAO59858

Hipparcos Catalogue HIP34693

Durchmusterung Catalogue BD+30 1439

General Catalogue of Variable Stars 3437

Aitken Double Star Catalogue ADS5846

Visibility from Your Location

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

Azimuth: 59.8° RISE 7:01

Max altitude: 68.7° TRANSIT 16:06

Azimuth: 300.2° SET 1:15

Set Location

Other stars in Gemini