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A Complete Guide to the Solar System and the Night Sky
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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 7:49  
clear_day Transit: 11:49  
SunsetSet: 15:50 south
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All Constellations » Taurus » 

Prima Hyadum - γ Tauri (gamma Tauri)

Altitude: -10.3°   Azimuth: 311.9°   Direction: North-West

Prima Hyadum, also designated as γ Tauri (gamma Tauri), is a variable hypergiant star in the constellation of Taurus.

Prima Hyadum visual magnitude is 3.65. Because of its moderate brightness, Prima Hyadum 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 Prima Hyadum:


Prima Hyadum - γ Tauri (gamma Tauri) is below the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: -10.3°
Azimuth: 311.9°
Direction: North-West

Celestial coordinates and finder chart of Prima Hyadum

Prima Hyadum 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 Prima Hyadum are provided in the following table:

04h 19m 47s
+15° 37’ 38”

The simplified sky map below shows the position of Prima Hyadum in the sky:

Finder chart Prima Hyadum - γ Tauri (gamma Tauri) star
Simplified finder chart for Prima Hyadum - γ Tauri (gamma Tauri).

Visibility of Prima Hyadum from your location

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

Today's Prima Hyadum - γ Tauri (gamma Tauri) rise, transit and set times from Greenwich, United Kingdom edit_location_alt are the following (all times relative to the local timezone Europe/London):

Azimuth: 74.4°
Max altitude: 54.1°
Azimuth: 285.6°

Digitized Sky Survey image of Prima Hyadum

The image below is a photograph of Prima Hyadum 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 Prima Hyadum is 0.115 arcsec per year in Right Ascension and -0.025 arcsec per year in Declination and the associated displacement for the next 1000 years is represented with the red arrow.

Image of Prima Hyadum - γ Tauri (gamma Tauri) star
DSS2 image of Prima Hyadum. The red arrow shows the motion of Prima Hyadum during the next 1000 years (1.92 arcmin in Right Ascension and -0.42 arcmin in declination);

Distance of Prima Hyadum from the Sun and relative movement

Prima Hyadum is distant 153.99 light years from the Sun and it is moving far from the Sun at the speed of 39 kilometers per second.

47.24 pc
153.99 ly
39 km/s
0.115 arcsec/year
-0.025 arcsec/year

Spectral properties of Prima Hyadum

Prima Hyadum belongs to spectral class K0 and has a luminosity class of III corresponding to a hypergiant star.


The red dot in the diagram below shows where Prima Hyadum is situated in the Hertzsprung–Russell diagram.

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

Alternative designations of Prima Hyadum

Prima Hyadum
γ Tauri
(gamma Tauri)