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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: 7:44  
clear_day Transit: 11:48  
SunsetSet: 15:51 south
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All Constellations » Aquarius » 

Sadalsuud - β Aquarii (beta Aquarii)

Altitude: -29.5°   Azimuth: 58.0°   Direction: East-North-East

Sadalsuud, also designated as β Aquarii (beta Aquarii), is a multiple hypergiant star in the constellation of Aquarius.

Sadalsuud visual magnitude is 2.91. Thanks to its high brightness, Sadalsuud is clearly visible when observed from locations with dark skyes, and should be also quite easily visible from light polluted areas.

The table below summarizes the key facts about Sadalsuud:


Sadalsuud - β Aquarii (beta Aquarii) is below the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: -29.5°
Azimuth: 58.0°
Direction: East-North-East

Celestial coordinates and finder chart of Sadalsuud

Sadalsuud 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 Sadalsuud are provided in the following table:

21h 31m 33s
-05° 34’ 15”

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

Finder chart Sadalsuud - β Aquarii (beta Aquarii) star
Simplified finder chart for Sadalsuud - β Aquarii (beta Aquarii).

Visibility of Sadalsuud 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 Sadalsuud - β Aquarii (beta Aquarii) 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: 95.6°
Max altitude: 32.9°
Azimuth: 264.4°

Digitized Sky Survey image of Sadalsuud

The image below is a photograph of Sadalsuud 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 Sadalsuud is 0.021 arcsec per year in Right Ascension and -0.008 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of Sadalsuud - β Aquarii (beta Aquarii) star
DSS2 image of Sadalsuud. The red arrow shows the motion of Sadalsuud during the next 10000 years (3.50 arcmin in Right Ascension and -1.33 arcmin in declination);

Distance of Sadalsuud from the Sun and relative movement

Sadalsuud is distant 611.63 light years from the Sun and it is moving far from the Sun at the speed of 7 kilometers per second.

187.62 pc
611.63 ly
7 km/s
0.021 arcsec/year
-0.008 arcsec/year

Spectral properties of Sadalsuud

Sadalsuud belongs to spectral class G0 and has a luminosity class of I corresponding to a hypergiant star.


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

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

Sadalsuud star system properties

Sadalsuud 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 Sadalsuud double sysyem:

35.5 arcsec

Alternative designations of Sadalsuud

β Aquarii
(beta Aquarii)