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: 4:45  
clear_day Transit: 12:57  
SunsetSet: 21:10 south
sunny DaytimeWhat's Visible Now
All Constellations » Aquarius » 

σ Aquarii (sigma Aquarii)

Altitude: 27.8°   Azimuth: 176.3°   Direction: South

σ Aquarii is a hypergiant star in the constellation of Aquarius.

σ Aquarii visual magnitude is 4.82. Because of its moderate brightness, σ Aquarii should be easily visible from locations with dark skyes, while it can be barely visible, or not visible at all, from skyes affected by light pollution.

The table below summarizes the key facts about σ Aquarii:


σ Aquarii (sigma Aquarii) is above the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: 27.8°
Azimuth: 176.3°
Direction: South

Celestial coordinates and finder chart of σ Aquarii

σ Aquarii 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 σ Aquarii are provided in the following table:

22h 30m 38s
-10° 40’ 41”

The simplified sky map below shows the position of σ Aquarii in the sky:

Finder chart σ Aquarii (sigma Aquarii) star
Simplified finder chart for σ Aquarii (sigma Aquarii).

Visibility of σ Aquarii 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 σ Aquarii (sigma 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: 100.7°
Max altitude: 27.8°
Azimuth: 259.3°
σ Aquarii (sigma Aquarii) is above the horizon from Greenwich, United Kingdom

Digitized Sky Survey image of σ Aquarii

The image below is a photograph of σ Aquarii 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 σ Aquarii is 0.003 arcsec per year in Right Ascension and -0.03 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of σ Aquarii (sigma Aquarii) star
DSS2 image of σ Aquarii. The red arrow shows the motion of σ Aquarii during the next 10000 years (0.50 arcmin in Right Ascension and -5.00 arcmin in declination);

Distance of σ Aquarii from the Sun and relative movement

σ Aquarii is distant 265.26 light years from the Sun and it is moving far from the Sun at the speed of 11 kilometers per second.

81.37 pc
265.26 ly
11 km/s
0.003 arcsec/year
-0.03 arcsec/year

Spectral properties of σ Aquarii

σ Aquarii belongs to spectral class A0 and has a luminosity class of IV corresponding to a hypergiant star.


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

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

Alternative designations of σ Aquarii

σ Aquarii
(sigma Aquarii)