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: 4:46  
clear_day Transit: 12:56  
SunsetSet: 21:07 south
sunny DaytimeWhat's Visible Now
All Constellations » Apus » 


Altitude: -55.1°   Azimuth: 157.1°   Direction: South-South-East

HR6731 is a double giant star in the constellation of Apus.

HR6731 visual magnitude is 5.86. Because of its reltive faintness, HR6731 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 HR6731:


HR6731 is below the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: -55.1°
Azimuth: 157.1°
Direction: South-South-East

Celestial coordinates and finder chart of HR6731

HR6731 is situated close to the southern celestial pole and, as such, it is easilty visible for most part of the year from the southern hemisphere. Celestial coordinates for the J2000 equinox as well as galactic coordinates of HR6731 are provided in the following table:

18h 11m 15s
-75° 53’ 29”

The simplified sky map below shows the position of HR6731 in the sky:

Finder chart HR6731 star
Simplified finder chart for HR6731.

Visibility of HR6731 from your location

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

HR6731 is currently not visible from Greenwich, United Kingdom edit_location_alt

Digitized Sky Survey image of HR6731

The image below is a photograph of HR6731 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 HR6731 is 0.01 arcsec per year in Right Ascension and -0.295 arcsec per year in Declination and the associated displacement for the next 1000 years is represented with the red arrow.

Image of HR6731 star
DSS2 image of HR6731. The red arrow shows the motion of HR6731 during the next 1000 years (0.17 arcmin in Right Ascension and -4.92 arcmin in declination);

Distance of HR6731 from the Sun and relative movement

HR6731 is distant 253.11 light years from the Sun and it is moving far from the Sun at the speed of 15 kilometers per second.

77.64 pc
253.11 ly
15 km/s
0.01 arcsec/year
-0.295 arcsec/year

Spectral properties of HR6731

HR6731 belongs to spectral class K2 and has a luminosity class of III corresponding to a giant star.


The red dot in the diagram below shows where HR6731 is situated in the HertzsprungÔÇôRussell diagram.

HR Diagram
H-R diagram showing the position of HR6731. Attribution: Richard Powell / CC BY-SA

HR6731 star system properties

HR6731 is a visual double star which can be observed only with the help of very large telescopes. The table below shows key information about the HR6731 double sysyem:

25.9 arcsec

Alternative designations of HR6731