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public LocationGreenwich, United Kingdom
TimezoneEurope/London
Sunrise: 5:09 
Transit: 12:54 
Sunset: 20:41
sunny   (Daytime)   What's Visible Now?

ζ Herculis (zeta Herculis)

Altitude: 1.2°   Azimuth: 35.4°   Direction: North-East

ζ Herculis is a variable and double hypergiant star in the constellation of Hercules.

ζ Herculis visual magnitude is 2.81. Thanks to its high brightness, ζ Herculis 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 ζ Herculis is -0.47 arcsec per year in Right Ascension and 0.394 arcsec per year in Declination and the associated displacement for the next 1000 years is represented with the red arrow.

Image of ζ Herculis (zeta Herculis) star
DSS2 image of ζ Herculis. The red arrow shows the motion of ζ Herculis during the next 1000 years (-7.83 arcmin in Right Ascension and 6.57 arcmin in declination);

Key facts about ζ Herculis

2.81
Hypergiant

ζ Herculis (zeta Herculis) is above the horizon from Greenwich, United Kingdom.

Altitude: 1.2°
Azimuth: 35.4°
Direction: North-East

Celestial coordinates and finder chart of ζ Herculis

ζ Herculis is situated north of the celestial equator, as such, it is more easily visible from the northern hemisphere. Celestial coordinates for the J2000 equinox as well as galactic coordinates of ζ Herculis are provided in the following table:

16h 41m 17s
+31° 36’ 11”
52.66°
40.28°
Hercules

The simplified sky map below shows the position of ζ Herculis in the sky:

Finder chart ζ Herculis (zeta Herculis) star
Simplified finder chart for ζ Herculis (zeta Herculis).

Visibility of ζ Herculis from your location

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

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

Azimuth: 58.4°
Max altitude: 70.1°
Azimuth: 301.6°

Distance of ζ Herculis from the Sun and relative movement

ζ Herculis is distant 35.19 light years from the Sun and it is moving towards the Sun at the speed of 70 kilometers per second.

10.80 pc
35.19 ly
-70 km/s
-0.47 arcsec/year
0.394 arcsec/year

Spectral properties of ζ Herculis

ζ Herculis belongs to spectral class G0 and has a luminosity class of IV corresponding to a hypergiant star.

2.64
G0IV
5778K

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

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

ζ Herculis star system properties

ζ Herculis is a visual double star which can be observed with the help of large telescopes. The table below shows key information about the ζ Herculis double sysyem:

2.81
5.41
2.6
1.1 arcsec

Alternative designations of ζ Herculis

ζ Herculis
(zeta Herculis)
40 Herculis
SAO65485
SAO65485
Gl 635 A