Name
The name of the star. This name has been created from combining the Catalog
Prefix, the Zone the star is found in, and the number of the star itself.
Prefix
The letters "BD" are included in each record in order to distinguish the BD
from all other machine-readable Durchmusterungen. Thus, all of the DM catalogs
can conceivably be combined into a single file, and the individual source
catalogs will still be identifiable.
Zone
The declination zone part of the BD number. The sign is always in byte 3, with
preceding zeros on single-digit zones where appropriate.
Star
Sequentially increasing star number within the specified zone.
RA
The Right Ascension of the object.
Dec
The Declination of the object.
LII
The galactic longitude of the object.
BII
The galactic latitude of the object.
Ident
Identification. This is derived from the code parameter.
Upper and lowercase codes are used. All lowercase letters represent
supplemental stars added to the catalog in the 1903 or later editions.
Uppercase letters and other characters are flags that indicate changes to the
original data or to the status of a star in the catalog. They have the
following meanings:
-------------------------------------------------------------------------------- "*" - Data have been corrected as a result of corrigenda, or there are special notes associated with the star. "?" - Existence of star was questioned by Kuestner in the 1903 edition or in one of his or Sticker's corrigenda lists. Many of these stars contain the "M" flag instead of the "?" because they were later investigated as a result of other lists (see "M" below). "D" - The star has been deleted in a later edition of the catalog. This was done by overstriking entries with horizontal lines. "M" - The star was noted as "missing" in lists published by Chandler (1896) or by Pickering (1907). --------------------------------------------------------------------------------
VMAG
The visual magnitude of the star.
Magnitude as estimated by the observer or magnitude code to denote non-numerical entries in the published catalogs. The following codes are used:
-------------------------------------------------------------------------------- 20.0 neb (denoting a nebula); 30.0 var (denoting variability); 40.0 nova or nova?; 50.0 cum (denoting the cumulative [integrated] magnitude estimate for a cluster of stars). --------------------------------------------------------------------------------
Class
BROWSE classification type. The classification is based on the `Type`
parameter, if one is available. Otherwise, one has been assigned, or the
classification is left blank.
Argelander, F. W. A. 1859-1862, Bonner Sternverzeichniss, erste bis dritte Sek- tion, Astronomischen Beobachtungen auf der Sternwarte des Koeniglichen Rhein., Friedrich-Wilhelms-Universitat zu Bonn, Bande 3-5.
Becker, F. 1951, Bonner Durchmusterung, Noerdlicher Teil, Deklinations-Zonen -1 bis +89 grade Sternverzeichnis, dritte, berichtigte Auflage (Bonn: Ferd. Duemmlers Verlag).