We use cookies to deliver essential features and to measure their performance. By using this site you accept our Privacy Policies.
A Complete Guide to the Solar System and the Night Sky
Help keep this site free and ads-free: donate now!
public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
SunriseRise: 5:39  
clear_day Transit: 12:56  
SunsetSet: 20:14
sunny DaytimeWhat's Visible Now?
All Constellations » Orion » 

Alnitak - ζ Orionis (zeta Orionis)

Altitude: -31.8°   Azimuth: 44.3°   Direction: North-East

Alnitak, also designated as ζ Orionis (zeta Orionis), is a variable and multiple supergiant star in the constellation of Orion.

Alnitak visual magnitude is 2.05, making it the 53th brightest star in the sky. Thanks to its high brightness, Alnitak is clearly visible when observed from locations with dark skies, and should be also quite easily visible from light polluted areas.

The proper motion of Alnitak is 0.003 arcsec per year in Right Ascension and -0.002 arcsec per year in Declination and the associated displacement for the next 100000 years is represented with the red arrow.

Image of Alnitak - ζ Orionis (zeta Orionis) star
DSS2 image of Alnitak. The red arrow shows the motion of Alnitak during the next 100000 years (5.00 arcmin in Right Ascension and -3.33 arcmin in declination);

Key facts about Alnitak

2.05
Supergiant

Alnitak - ζ Orionis (zeta Orionis) is below the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: -31.8°
Azimuth: 44.3°
Direction: North-East

Celestial coordinates and finder chart of Alnitak

Alnitak 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 Alnitak are provided in the following table:

05h 40m 45s
-01° 56’ 34”
206.45°
-16.59°
Orion

The simplified sky map below shows the position of Alnitak in the sky:

Finder chart Alnitak - ζ Orionis (zeta Orionis) star
Simplified finder chart for Alnitak - ζ Orionis (zeta Orionis).

Visibility of Alnitak 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 Alnitak - ζ Orionis (zeta Orionis) 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: 91.9°
Max altitude: 36.6°
Azimuth: 268.1°

Distance of Alnitak from the Sun and relative movement

Alnitak is distant 817.04 light years from the Sun and it is moving far from the Sun at the speed of 18 kilometers per second.

250.63 pc
817.04 ly
18 km/s
0.003 arcsec/year
-0.002 arcsec/year

Spectral properties of Alnitak

Alnitak belongs to spectral class O9 and has a luminosity class of I corresponding to a supergiant star.

-4.95
O9I
13831K

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

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

Alnitak star system properties

Alnitak 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 Alnitak double sysyem:

2.05
4.25
2.2
2.4 arcsec

Alternative designations of Alnitak

Alnitak
ζ Orionis
(zeta Orionis)
SAO132444
SAO132444