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public  Greenwich, UK Greenwich, UK  ⓘ
TimezoneEurope/London
Sunrise: 7:23 
Transit: 12:14 
Sunset: 17:05
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All Constellations » Hercules » 

21 Herculis

Below the horizon.  Rise: 0:30 | Tran: 7:02 | Set: 13:35
Alt: -11.39°   Az: 63.29°   Direction: East-North-East

21 Herculis is a star of spectral class A2 in the constellation of Hercules.

21 Herculis visual magnitude is 5.85. Because of its faintness, 21 Herculis is visible to the naked eye only from locations with very dark skies, while it is not visible at all from skies affected by light pollution.

Image of 21 Herculis star
DSS2 image of 21 Herculis. The red arrow shows the motion of 21 Herculis during the next 10000 years (0.50 arcmin in Right Ascension and 2.33 arcmin in declination);

Celestial Coordinates

Apparent

16h 25m 24s
+06° 53’ 29”
16h 07m 33s
08h 32m 58s

J2000

16h 24m 10s
+06° 56’ 53”

Galactic Coordinates

21.3°
35.77°

Finder Chart

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Finder chart for 21 Herculis.

Magnitude, Color, Spectral Class

5.85
21 Herculis is also a Sr chemically peculiar star.

0.75
A2
10252K

The red dot in the diagram below shows where 21 Herculis is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of 21 Herculis. Attribution: Richard Powell / CC BY-SA

Distance, Radial Speed, Proper Motion

21 Herculis is distant 341.36 light years from the Sun and it is moving towards the Sun at the speed of 33 kilometers per second.

104.71
341.36
-33 km/s
0.003 arcsec/y
0.014"/y

Alternative Designations

21 Herculis
SAO121568
SAO121568

Visibility from Your Location

Today's 21 Herculis rise, transit and set times from Greenwich, UK are the following (all times relative to the local timezone Europe/London):

Azimuth: 83.1°
Max altitude: 45.4°
Azimuth: 276.9°