I/146       Positions and Proper Motions (Roeser+ 1988)                        
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Catalogue of Positions and Proper Motions
    Roeser S., Bastian U.
    
    =1988A&AS...74..449R
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ADC_Keywords: Positional data; Proper motions

Description:
    PPM North gives J2000 positions and proper motions of 181,731
    stars north of -2.5 degrees declination. Its main purpose is to 
    provide a convenient, dense, and accurate net of astrometric 
    reference stars that represents the new IAU (1976) coordinate 
    system on the sky. The mean epoch is near 1931. The average mean 
    errors of the positions and proper motions are 0.27" and 0.43"/cen. 
    On the average six measured positions are available per star; 1064 
    stars do not have sufficient redundancies to resolve discrepancies.
    In addition to the positions and proper motions, the PPM (North)
    contains the BD number, the magnitude, the spectral type, the number
    of positions included, the mean error of each component of the
    position and proper motion, the weighted mean epoch in each
    coordinate, the numbers in the SAO, HD, and AGK3 catalogs, and 
    various standard notes.  In addition a number of individual notes 
    are given in the introduction.

    The PPM North consists of three files: a descriptive document 
    supplied by the authors for more detail regarding the scope, 
    construction, properties, and usage of PPM North; the data file 
    for the PPM North itself; and a version of PPM North in the format
    of the preliminary PPM North. See author supplied description for 
    more complete information.
    

File Summary:
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 FileName      Lrecl     Records         Explanations
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ReadMe            80           .         This file    
descrip.doc       80        1145         Authors' description
ppmnorth.dat     131      181731         Positions and Proper Motions - North
ppmnofmt.dat     138      181731         PPM North - in format of old PPM
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Byte-by-byte Description of file: ppmnorth.dat
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   Bytes  Format  Units     Label    Explanations  
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   2-  7   I6     ---       PPM     *Designation of the star
  10- 18   A9     ---       DM      *BD (zones -02 to -22), else CD
  20- 23   F4.1   mag       mag     *Magnitude
  25- 26   A2     ---       Sp      *Spectral type
  28- 29   I2     h         RAh      Right Ascension J2000 (hours)
  31- 32   I2     min       RAm      Right Ascension J2000 (minutes)
  34- 39   F6.3   s         RAs      Right Ascension J2000 (seconds)
      42   A1     ---       DE-      Declination J2000 (sign)
  43- 44   I2     deg       DEd      Declination J2000 (degrees)
  46- 47   I2     arcmin    DEm      Declination J2000 (minutes)
  49- 53   F5.2   arcsec    DEs      Declination J2000 (seconds)
  56- 62   F7.4   s/yr      pmRA    *Proper motion in RA, J2000
  64- 69   F6.3   arcsec/yr pmDE    *Proper motion in DE, J2000
  71- 72   I2     ---       N       *Number of individual published positions used
  74- 75   I2     10mas     e_RA    *Mean error of RA
  77- 78   I2     10mas     e_DE    *Mean error of DE
  80- 83   F4.1   mas/yr    e_pmRA  *Mean error of pmRA
  85- 88   F4.1   mas/yr    e_pmDE  *Mean error of pmDE
  90- 94   F5.2   yr        EpRA    *Weighted mean epoch, RA and pmRA
  96-100   F5.2   yr        EpDE    *Weighted mean epoch, DE and pmDE
 102-107   I6     ---       SAO      [1/258997]? SAO Designation
 109-114   I6     ---       HD       [1/350000]? Henry Draper Designation
 117-125   A9     ---       CPD      Cape Photographic Durchmusterung Designation
     127   A1     ---       Flag1   *'P' - problem, 'C' - comment
     128   A1     ---       Flag2   *'D' - double star
     129   A1     ---       Flag3   *    - not used
     130   A1     ---       Flag4   *'F' - member of FK5
     131   A1     ---       Flag5   *'R' - remark, 'V' - V mag (CPC-2)
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Note on PPM: 
  Designation of the star in PPM South starting with No. 181732,
  see chapter 3 of the author's description file.

Note on DM:
  Designation of the star in the Bonner Durchmusterung (for zones from
  -02 to -22 degrees) or in the Cordoba Durchmusterung (zones -23 to
  -89 degrees).

Note on mag and Sp:
  See chapter 3 of description file.

Note on pmRA and pmDE:
  Proper motion in right ascension fro epoch and equinox J2000.0,
  on the system of FK5 given in seconds of time per Julian year.

Note on N:
  Number of individual published positions used for the
  derivation of the position and proper motion given.

Note on e_RA:              
  Mean error of right ascension at the mean epoch of right ascension,
  multiplied by the cosine of declination, given in units of #0.01
  seconds of arc.

Note on e_DE:
  Mean error of declination at the mean epoch of declination, given in
  units of #0.01 seconds of arc.

Note on e_pmRA:
  Mean error of the proper motion in right ascension, multiplied by
  the cosine of declination, given in units of 0.001 seconds of arc
  per Julian year.

Note on e_pmDE:
  mean error of the proper motion in declination given in units of
  0.001 seconds of arc per Julian year

Note on EpRA:
  Weighted mean epoch of the measured positions used for the
  derivation of RA and pmRA, given in years since 1900.0.

Note on EpDE:
  Weighted mean epoch of the measured positions used for the
  derivation of DE and pmDE, given in years since 1900.0.

Note on Flag1: 
  P - problem case, preferably not to be used as astrometric
      reference star.  
  C - a critical comment is given in the List of Critical Comments. 
      Not to be used as astrometric reference star.

Note on Flag2:
  D - double star, preferably not to be used as astrometric
      reference star.
  
Note on Flag3:
  Not used, void for consistency with PPM (north).
  
Note on Flag4:
  F - member of FK5, mostly bright stars, original FK5 data
      are given.
  
Note on Flag5:
  R - a remark is given in the List of Remarks on Individual
      Stars.
  V - the magnitude is a photographic V magnitude copied from
      CPC-2.
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Byte-by-byte Description of file: ppmnofmt.dat
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   Bytes   Format   Units            Label      Explanations  
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   2-  4    A3      ---              cat        The catalog prefix 'PPM'
   5- 10    I6      ---              PPM        Designation of the star
  11- 16    F6.1    mag              mag        Magnitude
  19- 20    A2      ---              Sp         Spectral type
      22    A1      ---              Flag1     *Problem flag
  24- 38    F15.8   rad              RA1950     RA equinox and epoch B1950, FK4
  40- 54    F15.8   rad              DE1950     DE equinox and epoch B1950, FK4
  56- 67    F12.5   0.01rad/yr       pmRA1950   Proper motion in RA, B1950, FK4
  69- 80    F12.5   0.01rad/yr       pmDE1950   Proper motion in DE, B1950, FK4
  82- 96    F15.8   rad              RA         RA equinox and epoch J2000, FK5
  98-112    F15.8   rad              DE         DE equinox and epoch J2000, FK5
 114-125    F12.5   0.01rad/yr       pmRA       Proper motion in RA, J2000, FK5
 127-138    F12.5   0.01rad/yr       pmDE       Proper motion in DE, J2000, FK5
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Note on Flag1: 
  P - problem case, preferably not to be used as astrometric
      reference star.  
  C - a critical comment is given in the List of Critical Comments. 
      Not to be used as astrometric reference star.
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(End)                             Gail L. Schneider [NSSDC/ADC]    14-Nov-1994