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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 7:41  
clear_day Transit: 11:47  
SunsetSet: 15:53 south
wb_twilight Civil TwilightWhat's Visible Now?
All Constellations »  Andromeda »  Deep Sky Objects » 

Messier 31 (Andromeda Galaxy) - Spiral Galaxy in Andromeda

Altitude: 2.8°   Azimuth: 356.3°   Direction: North

Messier 31 is a Spiral Galaxy in the Andromeda constellation. Messier 31 is situated north of the celestial equator and, as such, it is more easily visible from the northern hemisphere.

Messier 31
Galaxy
Andromeda

Messier 31 is above the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: 2.8°
Azimuth: 356.3°
Direction: North

See also Messier 31 rise and set times.

Given its visual magnitude of 3.44, Messier 31 is visible to the naked eye under a clear and dark sky, or with the help of a small binocular.

Available Resources for Messier 31 (Andromeda Galaxy) - Spiral Galaxy in Andromeda

Photometric information of Messier 31

The following table lists the magnitude of Messier 31 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).

4.36
3.44
2.09
1.28
0.98

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

The surface brightess reported below is an indication of the brightness per unit of angular area of Messier 31.

23.63 mag/arcsec2

Apparent size of Messier 31

The following table reports Messier 31 apparent angular size. The green area displayed on top of the DSS2 image of Messier 31 is a visual representation of it.
177.83 arcmin
69.66 arcmin
35°

Digitized Sky Survey image of Messier 31

The image below is a photograph of Messier 31 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 5.9276666666667x5.9276666666667 degrees (355.66x355.66 arcmins).

Image of Messier 31 (Andromeda Galaxy) - Spiral Galaxy in Andromeda star
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DSS2 image of Messier 31 in the Red band. The green region on the image is a representation of the major (177.83 arcmin) and minor (69.66 arcmin) axes of the object's apparent size.

Messier 31 (Andromeda Galaxy) - Spiral Galaxy in Andromeda morphological classification

Messier 31 (Andromeda Galaxy) - Spiral Galaxy in Andromeda is classified as Spiral (SAb) according to the Hubble and de Vaucouleurs galaxy morphological classification. The diagram below shows a visual representation of the position of Messier 31 (Andromeda Galaxy) - Spiral Galaxy in Andromeda in the Hubble de Vaucouleurs sequence.

Messier 31 (Andromeda Galaxy) - Spiral Galaxy in Andromeda
Visualization of the morphological classification of Messier 31 (Andromeda Galaxy) - Spiral Galaxy in Andromeda, Spiral (SAb).
Credits for the background image: Antonio Ciccolella / M. De Leo / CC BY

Celestial coordinates and finder chart of Messier 31

Celestial coordinates for the J2000 equinox of Messier 31 are provided in the following table:

00h 42m 43s
+41° 16’ 08”

The simplified sky charts below show the position of Messier 31 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 31 (Andromeda Galaxy) - Spiral Galaxy in Andromeda star
Simplified finder chart for Messier 31 (Andromeda Galaxy) - Spiral Galaxy in Andromeda.

Finder chart Messier 31 (Andromeda Galaxy) - Spiral Galaxy in Andromeda star
Simplified finder chart for Messier 31 (Andromeda Galaxy) - Spiral Galaxy in Andromeda.

Rise ans set times of Messier 31 from your location

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

Messier 31 (Andromeda Galaxy) - Spiral Galaxy in Andromeda is circumpolar and transits at 20:01 UTC (altitude: 79.8°)