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public  Greenwich, UK Greenwich, UK  ⓘ
TimezoneEurope/London
Sunrise: 5:01 
Transit: 12:56 
Sunset: 20:52
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All Constellations »  Scorpius »  Deep Sky Objects » 

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

Below the horizon.  Rise: 1:03 | Tran: 2:59 | Set: 4:55
Alt: -0.67°   Az: 205.61°   Direction: South-South-West

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. 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.

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 0.7400x0.7400 degrees (44.40x44.40 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

Apparent

17h 55m 32s
-34° 47’ 45”
02h 07m 01s
20h 02m 34s

J2000

17h 53m 51s
-34° 47’ 34”

Finder Chart

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°.

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

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

Photometric Information

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

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

Rise and Set Times

Location: Greenwich, UK
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, UK are the following (all times relative to the local timezone Europe/London):

Azimuth: 124.8°
Max altitude: 3.7°
Azimuth: 235.2°