Your Guide to the Solar System and the Night Sky
Donate now! You'll help cover server costs, enhance the site and keep it ad-free.
public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 4:44  
clear_day Transit: 12:57  
SunsetSet: 21:11 south
wb_twilight Civil TwilightWhat's Visible Now
All Constellations » Aquarius » 

18 Aquarii

Altitude: -25.4°   Azimuth: 78.4°   Direction: East-North-East

18 Aquarii is a variable and double main-sequence star in the constellation of Aquarius.

18 Aquarii visual magnitude is 5.49. Because of its reltive faintness, 18 Aquarii 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 18 Aquarii:


18 Aquarii is below the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: -25.4°
Azimuth: 78.4°
Direction: East-North-East

Celestial coordinates and finder chart of 18 Aquarii

18 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 18 Aquarii are provided in the following table:

21h 24m 11s
-12° 52’ 41”

The simplified sky map below shows the position of 18 Aquarii in the sky:

Finder chart 18 Aquarii star
Simplified finder chart for 18 Aquarii.

Visibility of 18 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 18 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: 102.9°
Max altitude: 25.6°
Azimuth: 257.1°
18 Aquarii is below the horizon from Greenwich, United Kingdom

Digitized Sky Survey image of 18 Aquarii

The image below is a photograph of 18 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 18 Aquarii is 0.091 arcsec per year in Right Ascension and 0.008 arcsec per year in Declination and the associated displacement for the next 1000 years is represented with the red arrow.

Image of 18 Aquarii star
DSS2 image of 18 Aquarii. The red arrow shows the motion of 18 Aquarii during the next 1000 years (1.52 arcmin in Right Ascension and 0.13 arcmin in declination);

Distance of 18 Aquarii from the Sun and relative movement

18 Aquarii is distant 156.73 light years from the Sun and it is moving far from the Sun at the speed of 8 kilometers per second.

48.08 pc
156.73 ly
8 km/s
0.091 arcsec/year
0.008 arcsec/year

Spectral properties of 18 Aquarii

18 Aquarii belongs to spectral class F1 and has a luminosity class of V corresponding to a main-sequence star.


The red dot in the diagram below shows where 18 Aquarii is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of 18 Aquarii. Attribution: Richard Powell / CC BY-SA

18 Aquarii star system properties

18 Aquarii 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 18 Aquarii double sysyem:

48.9 arcsec

Alternative designations of 18 Aquarii