Prefixes used:

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Astronomical objects are named (designated) by a bewildering array of seemingly arbitrary prefixes. I intend this page to be a helpful (though not scholarly) guide to the prefixes I use to designate the visible light objects I have photographed. Many descriptive catalogs are devoted to wavelengths that we can not 'see' (that normal film / ccd detectors can not record), such as radio waves, ultraviolet waves, x-rays, gamma rays, etc., so I will try to designate objects by a visible light catalogue.

Since telescopic Astronomy began as a visual observational science, objects are usually grouped by their visible (on photographs or at the eyepiece) morphology (apparent physical characteristics). The cataloging (grouping) of objects by some common characteristic is the primary source the the prefixes used in photographic astronomical nomenclature. For instance, a catalog of all galactic Planetary Nebulae (PK's), or all galactic HII regions (LBN's). Almost all objects have more than one designation (some have scores), because they have been cataloged by multiple characteristics or studies. As an example, the Supernova Remnant most commonly known a Messier 1 (or M 1, the first object in the catalogue by Charles Messier) is also known as NGC 1952, 3C144, LBN 833, Sh2-244, etc. The CDS lists 61 separate designations for Messier 1. Many objects are also known by their common names, mostly from the visual appearance at the telescope eyepiece (M 1 is called the "Crab Nebula").

Below is an alphabetical listing of the prefixes used on my site, along with a brief explanation of their origin.

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B | I | N | S

Abell --- George Abell cataloged faint Planetary Nebulae from a visual inspection of POSS I (Palomar Observatory Sky Survey, first survey) plates. I like photographing these Planetaries, so I include the Abell designation for these faint Planetaries (they also have PK designations). He also cataloged faint clusters of galaxies from the POSS I plates, which bear an AGC or RCG (Abell Galaxy Clusters or Catalogue of Rich Clusters of Galaxies) prefix.

Andromeda --- The constellation Andromeda. Some objects are simply designated by the order that they are discovered in a given constellation, or just the constellation they are in. Therefore; Andromeda I, Andromeda II, etc., or the Aquarius Dwarf, the Sagittarius Dwarf, etc.

B --- E. E. Barnard. 349 objects from the 1927 "A Photographic Atlas of Selected Regions of The Milky Way", the first photographic survey of the northern milky way to illustrate 'starless voids', which we now know to be clouds of gas or dust that hide the background star field. See here for the original images/information online.

Basel --- Basel Astronomical Institute. New Open Clusters. Latest is number 20.

Berkeley --- University of California at Berkeley. Open Clusters from university investigations of POSS I plates for faint, rich open star clusters. 90 known.

Ced --- S. Cederblad. 'Studies of bright diffuse galactic nebulae with special regard to their spatial distribution'.

Cr --- a catalog of open star clusters created by a Swedish astronomy graduate student - Per Arne Collinder - for his 1931 doctoral dissertation. ("On Structural Properties of Open Clusters and Their Spatial Distribution.")

Cz --- M. Czernik. 'New Open Clusters' listing.

DoDz --- Dolidze/Dzimselejsvili. A list of 34 neglected entries from star cluster catalogues located at relatively high galactic latitudes which appear to be candidate late stages of star cluster dynamical evolution (from a paper named 'Dissolving star cluster candidates').

DWB --- Dickel, Wendker, Bieritz. A catalog of Ha (Hydrogen Alpha) emission nebulae in the Cygnus X region. Most of these are faint to very faint photographic nebulae.

ESO --- European Southern Observatory. Southern hemisphere photographic survey from Chile.

GN --- Atlas of Galactic Nebulae. Compilation of milky way nebulous objects from the POSS I survey for north of -33 degrees declination, and from the ESO/SRC Atlas for south of -33 degrees declination.

IC --- Index Catalog. Additional objects to supplement the NGC catalog. Published in two installments (1895 and 1908). Objects mostly found through photography. See The NGC / IC Project for more details.

King --- I. King. A Harvard astronomers 'New Open (galactic) Clusters' listing. Latest number is 26.

LBN --- Lynd's' Catalog of Bright Nebulae. 1965 photographic catalog of HII regions from the POSS I red plates.

LDN --- Lynd's' Catalog of Dark Nebulae. 1962 photographic catalog of dark nebulae from the POSS I red plates.

M --- Charles Messier was a French amateur comet hunter active in the mid 1700's. He began listing nebulous objects that looked like comets, but did not change their nightly position in the sky; therefore where not comets. This visually compiled listing from several comet hunters contains some of the very best (biggest, brightest) examples of almost all classes of objects visible from the Northern hemisphere. Check out The Messier Catalog online.  Also see this translation of 'Charles Messier's Original Catalog of 1771'.

MCG --- Morphological Catalog of Galaxies. Comprehensive Soviet classification of galaxies based on the POSS I plates.

NGC --- 'New General Catalogue of Nebulae and Clusters of Stars'. The grand daddy of all visual catalogs. Published by John Dreyer in 1888, the NGC was an attempt to collect the many lists of that time into one 'comprehensive' master list. The two largest 'contributors' were list from Sir William and Sir John Herschel, from observations in the mid 1800's from both hemispheres. As with the IC catalog, see The NGC / IC Project for more details. Also, check out The Interactive NGC Catalog Online from SEDS. See the 'Details on Acronym' for NGC on the CDS.

PK --- L. Perek and L. Kohoutek. The 1967 'Catalogue of Galactic and Planetary Nebulae'. The first extensive catalog of the various later stages of stellar evolution (when stars shed their outer layers).

PNG --- Planetary Nebulae, Galactic coordinates. This designation is from 'The Strasbourg-ESO Catalogue of Galactic Planetary Nebulae'. This is the current 'state of the art' catalog of planetary nebula, published by the European Southern Observatory.

Parsamyan --- E. S. Parsamyan. From an Armenian astronomer's 1965 catalog.

Palomar --- Palomar Globular Clusters. Mostly very faint Globular Clusters found on the POSS I plates.

Sh2 --- S. Sharpless. From the second catalog of HII regions by S. Sharpless. Found from examining the red POSS I plates

UGC --- Uppsala General Catalogue of Galaxies. Based on the POSS I plates. Complete to a diameter of 1.0 arc minutes, north of -02 degrees 30 minutes of declination.

vdB --- Sidney van de Bergh. From the 1966 paper on 'A study of Reflection Nebulae'. Found from examining the blue POSS I plates.


See this 2004 .pdf compendium from J.C. Vickers of more prefix explanations

NOTE: Special mention goes to 'A Master List of Nonstellar Optical Astronomical Objects' (goes by the acronym MOL). This is a 1980 book that is a compendium of approximately 185,000 listings from 270 catalogs! A numeric listing by Right Ascension using epoch 1950.0 coordinates. I wish this was available on the web in a searchable database. See my Links page for a few sites that contain many (probably all) of the catalogs mentioned above.

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