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Designations & the Lookup Engine
Object designations (system-preferred designations) in Deep-Sky Planner follow IAU recommendations. This means that catalog mnemonics (the abbeviation used to identify a catalog) are taken from those recommended by the IAU, and the format includes a space between the mnemonic and the object number. The object designation matching engine (described below) can usually distinguish a designation that omits the space between catalog mnemonic and object number, along with other variations that may occur.
[Note that User Designations (user-preferred designations) are not required to follow IAU recommendations. They can contain the designation that is meaningful to the user.]
The designation matching engine can also match some catalog mnemonics that are in common use but not recommended by the IAU. For example, the IAU recommends 'Barn' for the Barnard Catalog of Dark Nebulae, but 'B' is in common use so it is recognized. Other common variations include C = Caldwell, M = Messier, I = IC, N = NGC. When a designation is recognized, it is normally 'sanitized' by Deep-Sky Planner so that it appears in the correct form as recommended by the IAU. This is the system's preferred object designation.
Another commonly encountered problem illustrates why Deep-Sky Planner uses IAU recommended designation format. Consider an object named Abell 55. What should a designation lookup provide, the galaxy cluster or the planetary nebula? The IAU distinguishes this case by recommending the mnemonic 'ACO' for the galaxy cluster. Further, the Abell planetary nebulae catalog is actually a list of 86 planetaries taken from an article in Astrophysical Journal 1 and is not available in Deep-Sky Planner as a separate catalog. The nebula is present in Deep-Sky Planner's database, however, within the Strasbourg-ESO Planetary Nebula (PNG) catalog, and it is recognized as a common name of PNG 033.0-05.3.
Looking Up Objects: The Designation Matching Engine
You can look up an object in the database by designation or a common name. Deep-Sky Planner has a pattern matching engine that attempts to match an object designation entered by the user to an entry in the database. The engine is not a mind-reader, but it can understand some common mismatching problems that may occur in typical user entry.
The matching engine can ignore case mismatches, missing or extra embedded spaces (with some necessary exceptions) 2 and missing or extra leading zeroes 3. Wildcard characters * and ? are also supported. The engine can also match most variable stars named with the Argelander variable star naming system, i.e., R Lep rather than GCVS R Lep.
This means that you may look up 'crab*' and find entries such as Crab nebula. Please note that searching for 'hind*' matches entries in the deep-sky catalog so further matches in the star catalog are not retrieved. In this case, the engine finds Hind's variable nebula (NGC 1545, NGC 1546) but not Hind's Crimson Star (GCVS R Lep).
You may search for:
▪planet name - names of the major planets and Pluto
▪asteroid name - names of the brightest asteroids can be located by name alone, e.g., Juno. If this type of search fails, enter the full asteroid designation, e.g., (3) Juno.
▪comet name - full designation of the comet is recommended, e.g. C/2012 A1 (PANSTARRS). Note that the wildcard character is useful at the end of the search text, e.g. C/2012 A1*.
▪catalog designation (e.g., M 101 or GCVS R And)
▪Bayer or Flamsteed numbered stars, e.g. Beta Per. Including an asterisk after the constellation abbreviation in a Bayer designation is recommended, e.g., Epsilon* Lyr.
▪variable star designation, e.g., R And
▪common name (e.g. Crab *)
Notes:
1 The Abell planetaries are listed in the article "Properties of Some Old Planetary Nebulae", Astrophysical Journal 144 (April 1966): p 259.
2 The pattern matching engine requires a space between catalog and object number in Herschel (H) and Herschel 2 (H2) designations.
3 Catalogs that designate objects by galactic longitude & latitude or by POSS plate number cannot have missing digits in their designations because each digit is significant. These catalogs are: HB93, MCG, PNG, SNR; CCDM, GCVS, WDS
Help file version 9.2.3.0 ▪ Copyright © 2024-2026 Knightware, LLC
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