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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 6:59  
clear_day Transit: 12:48  
SunsetSet: 18:36 south
sunny DaytimeWhat's Visible Now
All Constellations »  Scorpius »  Deep Sky Objects » 

Messier 7 (Ptolemy's Cluster) - Open Cluster in Scorpius

Altitude: -26.1°   Azimuth: 113.9°   Direction: East-South-East

Messier 7 is a Open Cluster in the Scorpius constellation. Messier 7 is situated south of the celestial equator and, as such, it is more easily visible from the southern hemisphere.

Messier 7
Open Cluster
Scorpius

Messier 7 is below the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: -26.1°
Azimuth: 113.9°
Direction: East-South-East

See also Messier 7 rise and set times.

Given its visual magnitude of 3.3, Messier 7 is visible to the naked eye under a clear and dark sky, or with the help of a small binocular.

Available Resources for Messier 7 (Ptolemy's Cluster) - Open Cluster in Scorpius

Photometric information of Messier 7

The following table lists the magnitude of Messier 7 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).

3.45
3.3

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

Apparent size of Messier 7

The following table reports Messier 7 apparent angular size. The green area displayed on top of the DSS2 image of Messier 7 is a visual representation of it.
22.2 arcmin
22.2 arcmin

Digitized Sky Survey image of Messier 7

The image below is a photograph of Messier 7 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 0.74x0.74 degrees (44.4x44.4 arcmins).

Image of Messier 7 (Ptolemy's Cluster) - Open Cluster in Scorpius star
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DSS2 image of Messier 7 in the Red band. The green region on the image is a representation of the major (22.2 arcmin) and minor (22.2 arcmin) axes of the object's apparent size.

Celestial coordinates and finder chart of Messier 7

Celestial coordinates for the J2000 equinox of Messier 7 are provided in the following table:

17h 53m 51s
-34° 47’ 34”

The simplified sky charts below show the position of Messier 7 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 7 (Ptolemy's Cluster) - Open Cluster in Scorpius star
Simplified finder chart for Messier 7 (Ptolemy's Cluster) - Open Cluster in Scorpius.

Finder chart Messier 7 (Ptolemy's Cluster) - Open Cluster in Scorpius star
Simplified finder chart for Messier 7 (Ptolemy's Cluster) - Open Cluster in Scorpius.

Rise ans set times of Messier 7 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 7 (Ptolemy's Cluster) - Open Cluster in Scorpius 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: 124.8°
Max altitude: 3.7°
Azimuth: 235.2°