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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
SunriseRise: 6:04  
clear_day Transit: 12:06  
SunsetSet: 18:09
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All Constellations »  Sagittarius »  Deep Sky Objects » 

Messier 18 (Black Swan) - Open Cluster in Sagittarius

Altitude: 17.9°   Azimuth: 205.4°   Direction: South-South-West

Messier 18 is a Open Cluster in the Sagittarius constellation. Messier 18 is situated close to the celestial equator and, as such, it is at least partly visible from both hemispheres in certain times of the year.

The image below is a photograph of Messier 18 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).

Image of Messier 18 (Black Swan) - Open Cluster in Sagittarius star
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DSS2 image of Messier 18 in the Red band. The green region on the image is a representation of the major (6 arcmin) and minor (6 arcmin) axes of the object's apparent size.

Key facts about Messier 18

Messier 18
Open Cluster
Sagittarius

Messier 18 is above the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: 17.9°
Azimuth: 205.4°
Direction: South-South-West

See also Messier 18 rise and set times.

Given its visual magnitude of 6.9, Messier 18 is visible with the help of a small binocular.

Available Resources for Messier 18 (Black Swan) - Open Cluster in Sagittarius

Photometric information of Messier 18

The following table lists the magnitude of Messier 18 in different bands of the electomagnetic spectrum (when available), from the B band (445nm wavelength, corresponding to the Blue color), to the V band ( 551nm wavelength, corresponding to Green/Yellow color), to the J, H, K bands (corresponding to 1220nm, 1630nm, 2190nm wavelengths respectively, which are colors not visible to the human eye).

7.24
6.9

For more information about photometry in astronomy, check the photometric system article on Wikipedia.

Apparent size of Messier 18

The following table reports Messier 18 apparent angular size. The green area displayed on top of the DSS2 image of Messier 18 is a visual representation of it.
6 arcmin
6 arcmin

Celestial coordinates and finder chart of Messier 18

Celestial coordinates for the J2000 equinox of Messier 18 are provided in the following table:

18h 19m 58s
-17° 06’ 06”

The simplified sky charts below show the position of Messier 18 in the sky. The first chart has a field of view of 60° while the second one has a field of view of 10°.

Finder chart Messier 18 (Black Swan) - Open Cluster in Sagittarius star
Simplified finder chart for Messier 18 (Black Swan) - Open Cluster in Sagittarius.

Finder chart Messier 18 (Black Swan) - Open Cluster in Sagittarius star
Simplified finder chart for Messier 18 (Black Swan) - Open Cluster in Sagittarius.

Rise and set times of Messier 18 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 Messier 18 (Black Swan) - Open Cluster in Sagittarius 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: 107.1°
Max altitude: 21.4°
Azimuth: 252.9°