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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: 7:38  
clear_day Transit: 11:46  
SunsetSet: 15:54 south
sleep NighttimeWhat's Visible Now?
All Constellations » Hercules » 

100 Herculis

Altitude: 27.6°   Azimuth: 278.1°   Direction: West

100 Herculis is a variable and multiple main-sequence star in the constellation of Hercules.

100 Herculis visual magnitude is 5.9. Because of its reltive faintness, 100 Herculis should be visible only from locations with dark skyes, while it is not visible at all from skyes affected by light pollution.

The table below summarizes the key facts about 100 Herculis:


100 Herculis is above the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: 27.6°
Azimuth: 278.1°
Direction: West

Celestial coordinates and finder chart of 100 Herculis

100 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 100 Herculis are provided in the following table:

18h 07m 49s
+26° 05’ 51”

The simplified sky map below shows the position of 100 Herculis in the sky:

Finder chart 100 Herculis star
Simplified finder chart for 100 Herculis.

Visibility of 100 Herculis 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 100 Herculis 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: 63.9°
Max altitude: 64.6°
Azimuth: 296.1°

Digitized Sky Survey image of 100 Herculis

The image below is a photograph of 100 Herculis 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 100 Herculis is -0.002 arcsec per year in Right Ascension and 0.033 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of 100 Herculis star
DSS2 image of 100 Herculis. The red arrow shows the motion of 100 Herculis during the next 10000 years (-0.33 arcmin in Right Ascension and 5.50 arcmin in declination);

Distance of 100 Herculis from the Sun and relative movement

100 Herculis is distant 165.90 light years from the Sun and it is moving towards the Sun at the speed of 16 kilometers per second.

50.89 pc
165.90 ly
-16 km/s
-0.002 arcsec/year
0.033 arcsec/year

Spectral properties of 100 Herculis

100 Herculis belongs to spectral class A3 and has a luminosity class of V corresponding to a main-sequence star.


The red dot in the diagram below shows where 100 Herculis is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of 100 Herculis. Attribution: Richard Powell / CC BY-SA

Alternative designations of 100 Herculis

100 Herculis