Your Guide to the Solar System and the Night Sky
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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 6:54  
clear_day Transit: 12:49  
SunsetSet: 18:43 south
sunny DaytimeWhat's Visible Now
All Constellations » Hercules » 

101 Herculis

Altitude: -8.2°   Azimuth: 42.5°   Direction: North-East

101 Herculis is a giant star in the constellation of Hercules.

101 Herculis visual magnitude is 5.1. Because of its reltive faintness, 101 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 101 Herculis:


101 Herculis is below the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: -8.2°
Azimuth: 42.5°
Direction: North-East

Celestial coordinates and finder chart of 101 Herculis

101 Herculis 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 101 Herculis are provided in the following table:

18h 08m 52s
+20° 02’ 43”

The simplified sky map below shows the position of 101 Herculis in the sky:

Finder chart 101 Herculis star
Simplified finder chart for 101 Herculis.

Visibility of 101 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 101 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: 70.0°
Max altitude: 58.6°
Azimuth: 290.0°

Digitized Sky Survey image of 101 Herculis

The image below is a photograph of 101 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 101 Herculis is 0.008 arcsec per year in Right Ascension and -0.02 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of 101 Herculis star
DSS2 image of 101 Herculis. The red arrow shows the motion of 101 Herculis during the next 10000 years (1.33 arcmin in Right Ascension and -3.33 arcmin in declination);

Distance of 101 Herculis from the Sun and relative movement

101 Herculis is distant 320.87 light years from the Sun and it is moving towards the Sun at the speed of 16 kilometers per second.

98.43 pc
320.87 ly
-16 km/s
0.008 arcsec/year
-0.02 arcsec/year

Spectral properties of 101 Herculis

101 Herculis belongs to spectral class A8 and has a luminosity class of III corresponding to a giant star.


The red dot in the diagram below shows where 101 Herculis is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of 101 Herculis. Attribution: Richard Powell / CC BY-SA

Alternative designations of 101 Herculis

101 Herculis