BD (S0): Bonner Durchmusterung
FILES:
Name Magnitude range Dec (2000) range #Stars
bd70.s0 1.0 <= mag <= 7.0 -3 < Dec <= +90 8132
bd7180.s0 7.1 <= mag <= 8.0 -3 < Dec <= +90 17638
bd8185.s0 8.1 <= mag <= 8.5 -3 < Dec <= +90 23632
bd8690.s0 8.6 <= mag <= 9.0 -3 < Dec <= +90 54711
bd91a.s0 9.1 <= mag <= 9.9 +40 <= Dec <= +90 74795
bd91b.s0 9.1 <= mag <=10.0 +20 <= Dec < +40 68222
bd91c.s0 9.1 <= mag <=10.0 -3 < Dec <= +20 77544
bd_nomag.s0 NO MAGNITUDES -90 <= Dec <= +90 363
CONTENTS: Bonner Durchmusterung; NSSDC 1989 version (325037 stars)
DATASET: These files compose HyperSky dataset S-19, version 19941231. Availability on HyperSky CD-ROM: Vol. 2 (1995)
DESCRIPTION:
These datafiles contain the Bonner Durchmusterung (BD) star catalog. The BD (Argelander 1859-62, Kuestner 1903, Becker 1951, Schmidt 1968) is a visual survey of stars in the declination zones +89 to -01 degrees. The survey, completed by Argelander and his assistants in the years 1852-1861, was performed and the stars cataloged by allowing the telescope to drift along the mean declination of each zone and recording the positions and magnitudes of stars crosssing the transit line of each field.
The goal of the survey was to obtain a position and estimated visual magnitude for every star visible with the 78-mm Bonn telescope. Actual magnitude estimates were recorded to 0.1 mag for all stars down to 9.5 mag, with fainter stars being assigned to 9.5. Thus, the BD actually contains a rather large number of stars fainter than 10.0 mag. Positions are given to the nearest 0.1 sec in Right Ascension and 0.1 arcmin in Declination.
The National Space Science Data Center (NSSDC) 1989 machine-readable version of the BD is a result of collaborative efforts by the Centre de Donnees Astronomiques de Strasbourg, l'Observatoire de Nice, and the Astronomical Data Center (ADC) at the NASA/Goddard Space Flight Center. All corrigenda published in the original BD volumes were incorporated into the machine files, along with changes published by Kuestner and Sticker following the 1903 edition. In addition, stars indicated to be "missing" in published lists and verified by various techniques were flagged so that they could be omitted from computer plotted charts if desired. Stars deleted in the various errata lists were similarly flagged. The BD covers zones +89 to -01 (equinox 1855). BD zones -02 to -23 (known as the Southern Durchmusterung, or SD) were made available in a separate machine-readable catalog.
The HyperSky files are based on the version of the catalog available as ADC catalog #1122. The Southern Durchmusterung (ADC catalog #1119) is available in HyperSky dataset S-20.
DATA:
The HyperSky datafiles contain the following data from the BD catalog:
POSITION: Right Ascension and Declination are based on the 1855 catalog values, precessed to equinox 2000. The 1855 BD positions are given to 0.1 min of RA and 0.1 arcmin of Declination. Thus the precessed RA and Declination are also limited to this accuracy.
MAG: Visual magnitude estimate. Note that, despite the above remarks that no magnitudes fainter than 9.5 were assigned, some magnitudes are given as faint as 10.0. This may be due to later corrections to the catalog. Also note that the BD bright magnitude limit is 1.0. Stars brighter than 1.0 have been assigned this value, including for example Capella (ALPHA Aur) and Procyon (ALPHA CMi). Curiously, one such star, Betelgeuse (ALPHA Ori) is missing entirely from the BD.
TY: not provided, since no (spectral) types are given by the BD.
IDENTIFICATION: The BD number of the star, in the form +DD NNNN, where DD (+ or -) is the Declination zone number, and NNNN is the assigned number of the star within the Declination zone. A single code letter may be optionally be appended to this number. Lower case code letters represent supplemental (footnoted) stars added to the catalog in the 1903 or later editions. Upper case letters and other characters are flags that indicate changes to the original data or to the status of a star in the catalog. Notes and lists associated with these flags are available in the ADC catalog documentation. The codes have the following meanings:
* Data were 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). These entries were verified by R. A. Downes and at the ADC.
COMMENTS: A single comment line will appear only for stars in the file bd_nomag.s0, where the magnitude was replaced by a code. The code translation appears as a one-word comment, which can be one of "nebula", "variable", "nova", or "cluster".