Access to Astronomical Catalogues

← Click to display the menu
I/223              Algiers AC Zone Data Reduced to ACRS  (Urban+ 1995)

Algiers AC Zone Data Reduced to ACRS Urban S.E., Jackson E.S., Corbin T.E. <unpublished (1995)>
ADC_Keywords: Astrographic zones - 135; Combined data - 240; Cross identifications - 255; Finding lists - 280; Historical catalog - 343; Magnitudes, photographic - 380; Photographic catalog - 460; Plate areas - 645; Plate data - 650; Positional data - 660; Regional catalog - 705; Surveys - 975 Abstract: The U.S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue (AC) using a modern reference system, the ACRS, which represents the system of the FK5. The data from the Algiers Zone, whose plates are centered between declinations -2 and +4 degrees (eq. 1900), have been analyzed for scale, rotation, tilt, coma, magnitude equation, radial distortion and distortions introduced by the use of reseaux in the Carte du Ciel program. The result is a positional catalog of over 199,000 stars on eq. J2000.0, epoch of observation. The plate were exposed between 1891 and 1912. For cross-identification purposes, all stars have been matched with the Tycho Input Catalog (revised); those numbers have been added to each record. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file algac.dat 97 199713 Algiers AC stars reduced using ACRS notes 135 483 Notes on the AC/Tycho matches
See also: I/171 : the Astrographic Catalog Reference Stars (ACRS, Corbin et al., 1991) I/197 : Tycho Input Catalogue, Revised version (TIC, Egret et al., 1992) I/219 : Cape AC Zone (-41 to -51) Reduced to ACRS (Urban & Corbin, 1995) I/222 : San Fernando AC Zone (-3 to -9) Reduced to ACRS (Urban et al., 1995) I/224 : Oxford 1 AC Zone (+25 to +31) Reduced to ACRS (Urban et al., 1996) I/225 : Oxford 2 AC Zone (+32 to +33) Reduced to ACRS (Urban et al., 1996) I/226 : Vatican AC Zone (+55 to +64) Reduced to ACRS (Urban et al., 1996) I/227 : Paris AC Zone (+18 to +24) Reduced to ACRS (Urban et al., 1996) I/228 : Bordeaux AC Zone (+11 to +17) Reduced to ACRS (Urban et al., 1996) I/231 : Uccle AC Zone (+05 to +11) Reduced to ACRS (Urban et al., 1996) I/232 : Toulouse AC Zone (+34 to +35) Reduced to ACRS (Urban et al., 1996) Byte-by-byte Description of file: algac.dat
Bytes Format Units Label Explanations
1- 2 I2 h RAh Right Ascension J2000.0 (hours) 4- 5 I2 min RAm Right Ascension J2000.0 (minutes) 7- 12 F6.3 s RAs Right Ascension J2000.0 (seconds) 14 A1 --- DE- [±] Declination J2000.0 (sign) 15- 16 I2 deg DEd [0/5] Declination J2000.0 (degrees) 18- 19 I2 arcmin DEm Declination J2000.0 (minutes) 21- 25 F5.2 arcsec DEs Declination J2000.0 (seconds) 28- 32 F5.2 mag Bmag Magnitude from image diameter 34- 41 F8.3 yr Ep(RA) Mean epoch of position, RA 43- 50 F8.3 yr Ep(Dec) Mean epoch of position, Dec 51- 52 I2 --- Num Number of images used 53- 58 F6.3 arcsec e_RAs ?Mean error (Right Ascension) 59- 64 F6.3 arcsec e_DEs ?Mean error (Declination) 66- 73 I8 --- ISN *Internal Star Number ID 75- 82 I8 --- ACRS ?ACRS number 84- 92 I9 --- TICr ?Tycho Input Catalog (rev) number 94- 97 I4 --- NoteID *[1/412]? Note detailed in file notes
Note on ISN: The Internal Star Number, ISN, is used in the reduction process to identify all images of the same star that may appear on different plates. This is generated at U.S. Naval Observatory (USNO) and added on to the original x,y data. When the original data are released by USNO, this number can be used to link the original data to the final catalog. Note on NoteID: Detailed notes concerning possible errors in the AC/Tycho matches can be found in the file notes.
Byte-by-byte Description of file: notes
Bytes Format Units Label Explanations
1- 4 I4 --- NoteID [1/412]+= Number from NoteID in algac.dat 5-135 A131 --- Note Footnote for this star
References: New Reductions of the Astrographic Catalogue: Conventional Plate Adjustment of the Cape Zone, Urban S.E. and Corbin T.E. Astronomy and Astrophysics, January, 1996, in press The U.S. Naval Observatory Astrographic Catalog Project, Urban, S.E. and Corbin, T.E., Galactic and Solar System Optical Astrometry, ed. Morrison and Gilmore, Camb. Univ. Press, p. 11, 1994
(End) Sean E. Urban [U.S. Naval Observatory] 14-Dec-1995
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

catalogue service

© UDS/CNRS

Contact