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public LocationGreenwich, UK
TimezoneEurope/London
Sunrise: 4:58 
Transit: 13:04 
Sunset: 21:09
sunny   (Daytime)   What's Visible Now?
All Constellations »  Sagittarius »  Deep Sky Objects » 

Messier 21 - Open Cluster in Sagittarius

Below the horizon.  Rise: 19:41 | Tran: 23:35 | Set: 3:32
Altitude: -24.8°   Azimuth: 264.5°   Direction: West

Messier 21 is a Open Cluster in the Sagittarius constellation. Messier 21 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. Given its visual magnitude of 5.9, Messier 21 is easily visible with the help of a small binocular.

The image below is a photograph of Messier 21 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 0.5000x0.5000 degrees (30.00x30.00 arcmins).

Image of Messier 21 - Open Cluster in Sagittarius star
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DSS2 image of Messier 21 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.

Apparent Coordinates

18h 05m 42s
-22° 29’ 13”

J2000 Coordinates

18h 04m 13s
-22° 29’ 23”

Finder Chart

The simplified sky charts below show the position of Messier 21 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 21 - Open Cluster in Sagittarius star
Simplified finder chart for Messier 21 - Open Cluster in Sagittarius.

Finder chart Messier 21 - Open Cluster in Sagittarius star
Simplified finder chart for Messier 21 - Open Cluster in Sagittarius.

Photometric Information

The following table lists the magnitude of Messier 21 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).

5.9

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

Apparent Size

The following table reports Messier 21 apparent angular size. The green area displayed on top of the DSS2 image of Messier 21 is a visual representation of it.
6 arcmin
6 arcmin

Rise and Set Times

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

Today's Messier 21 - Open Cluster in Sagittarius rise, transit and set times from Greenwich, UK are the following (all times relative to the local timezone Europe/London):

Azimuth: 112.5°
Max altitude: 16.0°
Azimuth: 247.5°