We use cookies to deliver essential features and to measure their performance. Learn more.
We're free & ads-free thanks to your support
public LocationGreenwich, UK
Sunrise: 5:00 
Transit: 13:04 
Sunset: 21:07
wb_twilight   (Nautical Twilight)   What's Visible Now?
All Constellations » Hercules » 


Above the horizon.  Rise: 15:22 | Tran: 23:12 | Set: 7:06
Alt: 56.63°   Az: 151.92°   Direction: South-South-East

HR6638 is a sub-giant star of spectral class G5 in the constellation of Hercules.

HR6638 visual magnitude is 5.69. Because of its faintness, HR6638 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.

HR6638 is situated close to the celestial equator, as such, it is at least partly visible from both hemispheres in certain times of the year.

Image of HR6638 star
DSS2 image of HR6638. The red arrow shows the motion of HR6638 during the next 10000 years (4.33 arcmin in Right Ascension and 1.33 arcmin in declination);

Celestial Coordinates


17h 49m 27s
+20° 33’ 32”
22h 55m 46s
16h 45m 14s


17h 48m 24s
+20° 33’ 56”

Galactic Coordinates


Finder Chart

Finder chart HR6638 star
Simplified finder chart for HR6638.

Magnitude, Color, Spectral Class



The red dot in the diagram below shows where HR6638 is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of HR6638. Attribution: Richard Powell / CC BY-SA

Distance, Radial Speed, Proper Motion

HR6638 is distant 250.00 light years from the Sun and it is moving towards the Sun at the speed of 26 kilometers per second.

76.69 pc
250.00 ly
-26 km/s
0.026 arcsec/y
0.008 "/y

Alternative Designations


Visibility from Your Location

Today's HR6638 rise, transit and set times from Greenwich, UK are the following (all times relative to the local timezone Europe/London):

Azimuth: 69.4°
Max altitude: 59.1°
Azimuth: 290.6°