I/146 Positions and Proper Motions (Roeser+ 1988)

Catalogue of Positions and Proper Motions

Roeser S., Bastian U.

<Astron. Astrophys. Suppl. Ser. 74, 449 (1988)>

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:

Byte-by-byte Description of file: ppmnorth.dat

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.

Byte-by-byte Description of file: ppmnofmt.dat

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.

(End) Gail L. Schneider [NSSDC/ADC] 14-Nov-1994