MESSIER - Messier Nebulae
The Messier catalog object designation.
The NGC Number associated with the Messier observation. Sometimes, this is blank. Please refer to notes for suspected but unconfirmed NGC notations.
The Right Ascension of the object in the specified equinox.
The Declination of the object in the specified equinox.
The Galactic Longitude of the object.
The Galactic Latitude of the object.
A 3-character abbreviation identifying the constellation in which the object resides.
The angular size of the object, in arcminutes. For objects that are significantly non-circular, both the major axis M and the minor axis m are listed in the form M x m.
Most magnitudes are photoelectric visual values rounded to tenths. When these were not available, the approximate visual magnitudes were taken from M.V. Zombeck's 1982 compilation and other sources; such values have a colon, or, if originally rounded to the nearest whole value, have a '*' in the 'Vmag_Uncert' field.
A flag if the magnitude is uncertain. A ':' for values derived from other sources, and a '*' for values derived from other sources and rounded to the nearest whole number.
The object category. Di = diffuse nebula, Gb = globular cluster, OC = open cluster, Pl = Plantetary Nebula, E = eliptical galaxy, Ir = Irregular Galaxy, S = Spiral Galaxy.
Notes are frequently alternative names, but there are additonal notes on occasion.
The Browse classification type. The classification is based on the 'Type' parameter, if one is available.