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VI/30       Plate Centers of the ESO Sky Survey (Holmberg+ 1974)
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Plate Centers of the European Southern Observatory Sky Survey
    Holmberg E.B., Lauberts A., Schuster H.-E., West R.M.
    <Astron. Astrophys. Suppl. Ser. 18, 463 (1974)>
    =1974A&AS...18..463H
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ADC_Keywords: Surveys; Plate data

Description:
  The "ESO/SRC Atlas of the Southern Sky" is a major tool for, among
  other things, the optical identification of sources in non-optical
  wavelengths. It is useful to be able to identify the set of SAO
  stars in each ESO/SRC survey field both for possible source
  identifications and for astrometry. The dataset describes the
  ESO/SRC fields, including the coordinates of the centers. This
  catalog lists the 606 field centers for the ESO (B) Survey (also
  called the Quick Blue Survey). For each field are listed field ID,
  B1950 right ascension (hours and minutes) and declination (whole
  degrees) followed by right ascension and declination in radians. 

File Summary:
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 FileName       Lrecl  Records   Explanations
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ReadMe             80        .   This file
data.dat           52      606   Catalog Data
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Byte-by-byte Description of file: data.dat
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   Bytes  Format   Units   Label     Explanations
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   1-  3   I3      ---     FldNum    ? ESO/SRC Atlas of the Southern Sky field  
                                     number.
   7-  8   I2      h       RAh      *? Hours of right ascension.
  11- 12   I2      min     RAm      *? Minutes of right ascension.
      16   A1      ---     DE-       Sign of declination (always minus).
  17- 18   I2      deg     DEd      *? Degrees of declination.            
  22- 29   F8.5    rad     RArad    *? Right ascension in radians.      
  33- 40   F8.5    rad     DErad    *? Declination in radians.          
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Note on RAh, RAm, DEd:
  Nominal field center, equatorial coordinates (1950.0), in sexagesimal units.

Note on RArad, DErad:
  Nominal field center, equatorial coordinates (1950.0) in radians. 

REMARKS AND MODIFICATIONS:
  The file of plate centers (file 1 of this dataset) gives the nominal field
  centers of the ESO/SRC Atlas of the Southern Sky as listed in Holmberg et
  al. (1974).  This file was prepared by the Astronomical Data Center (ADC),
  NASA Goddard Space Flight Center. 
  The nominal centers were adopted, and one plate scale was adopted for all
  the fields.  This scale is 66.98 arc seconds/mm in the east-west direction
  and 67.26 arc seconds/mm in the north-south direction.  This scale was
  derived by measuring the distances between SAO stars on selected films and
  was tested by generating overlays with a Calcomp plotter.  The ability to
  efficiently generate such overlays for source identification was the primary
  reason for producing this dataset. 

REFERENCES:
  Holmberg, E. B., Lamberts, A., Schuster, H. E., and West, R. M. (1974).
    Astron.  Astrophys Suppl. pp. 463-489.
  Nagy, T. A. (1980). Astronomical Data Center Bulletin pp. 28-31.
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(End)                        C.-H. Joseph Lyu [Hughes STX/NASA]  16-Aug-1995