I/241 The N70E catalogue (Kolesnik, 1997)
A normal system of positions and proper motions in the equatorial zone
centred at epoch 1970.
Kolesnik Y.B.
<Mon. Not. R. Astron. Soc. 285, 1 (1997)>
=1997MNRAS.285....1K 1997MNRAS.285....1K
ADC_Keywords: Proper motions ; Positional data
Keywords: catalogues - astrometry - reference systems
Description:
The N70E catalogue provides improved mean positions and proper motions
for the 718 Basic fundamental stars from the FK5 catalogue in the
equatorial zone covering the declination range from -30 to +30 degrees.
The catalogue is resulted from revision of the FK5 system on the basis of
36 modern absolute and quasi-absolute catalogues and the four fundamental
catalogues FK3, FK4, GC, N30, and revision of FK5 individual
positions and proper motions by use of 52 catalogues distributed at the
time span from 1900 to 1993. Absolute orientation in space of N70E
catalogue is defined by the IAU (1976) system of astronomical constants.
Only the machine-readable version of the N70E catalogue is distributed.
It contains the positions and proper motions of the stars for the epoch
and equinox J2000.0, the mean epochs of individual observed right
ascensions and declinations used to determine the final positions,
and the mean errors of the final positions and proper motions for the
reported epochs.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
n70e 80 718 *The N70E catalogue
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Note on n70e: the ancillary data such as magnitudes, spectral types,
parallaxes, radial velocities, and cross identifications to other
catalogues designations can be extracted from the FK5 catalogue,
see I/149 Fifth Fundamental Catalogue (FK5) Part I.
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See also:
I/80 : Catalog of 5268 Standard Stars, Normal System N30 (Morgan 1952)
I/113 : General Catalogue of 33342 stars (GC) (Boss 1937)
I/143 : FK4 and FK4 Supplement (Fricke+ 1963)
I/149 : Fifth Fundamental Catalogue (FK5) Part I (Fricke+, 1988)
I/175 : Fifth Fundamental Catalogue (FK5) - Extension (Fricke+ 1991)
Byte-by-byte description of the file: n70e
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Bytes Format Units Label Explanations
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1- 4 I4 --- FK5 *FK5 number
6- 7 I2 h RAh Right ascension hours (J2000.0)
9- 10 I2 min RAm Right ascension minutes (J2000.0)
12- 18 F7.4 s RAs Right ascension seconds (J2000.0)
19- 27 F9.4 0.01s/yr pmRA Centennial proper motion in RA (J2000.0)
29 A1 --- DE- Sign of declination (Dec) (J2000.0)
30- 31 I2 deg DEd Declination degrees (J2000.0)
33- 34 I2 arcmin DEm Declination arcminutes (J2000.0)
36- 41 F6.3 arcsec DEs Declination arcseconds (J2000.0)
42- 50 F9.3 0.01arcsec/yr pmDE Proper motion in DE (J2000.0)
52- 56 F5.2 yr EpRA-1900 *Mean Epoch of individual observed RA
57- 60 F4.1 0.01arcsec e_RAs *Mean error in individual observed RA
61- 65 F5.1 0.1mas/yr e_pmRA *Mean error in individual observed pmRA
67- 71 F5.2 yr EpDE-1900 *Mean Epoch of individual observed DE
72- 75 F4.1 0.01arcsec e_DEs *Mean error in individual observed DE
76- 80 F5.1 0.1mas/yr e_pmDE *Mean error in individual observed pmDE
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Note on FK5 number:
Since the N70E catalogue represents revision of the FK5 system and
comprises only basic fundamental stars, the numeration have been
remained the same as it is adopted in the FK3, FK4 and FK5 catalogues.
The N70E catalogue, therefore, has not its own numbers. It should be
noted that the file is arranged not by right ascension, but by the FK5
number.
Note on EpRA-1900, EpDE-1900:
Mean epoch (-1900.0) of the individual observed right ascensions and
declinations as resulted from weighted random improvement of the FK5
positions.
Note on e_RAs, e_pmRA and e_DEs, e_pmDE:
The mean errors of the positions at the mean epoch and of the
corresponding proper-motion components, as obtained from the solution
of the normal equations within the derivations of individual positions
and proper motions. It should be emphasised that, by contrast to
conventional form of publication of catalogues which belong to FK
series, the errors in RAs and pmRA are given in arcseconds, not in
seconds of time.
(These mean errors do not include those of the N70E system which are
estimated about 2 times smaller, see the source reference. It should
be noted that the absolute orientation in space of N70E catalogue has
been kept from the FK5 system, therefore the errors of FK5 equinox and
equator and their secular variations are intrinsically embedded into
N70E coordinates.)
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Author's address:
Yuri B. Kolesnik
Institute of Astronomy of the Russian Academy of Sciences
48 Piatnitskaya St.
109017 Moscow, Russia
References:
Fricke, W., Schwan, H., & Lederle, T. (in collaboration with
Bastian, U., Bien, R., Burkhardt, G., du Mont, B., Hering, R.,
Jaehrling, R., Jahreiss, H., Roeser, S., Schwerdtfeger, H. M., &
Walter, H. G.) 1988, Fifth Fundamental Catalogue (FK5), Part I. The
Basic Fundamental Stars, Veroeff. Astron. Rechen-Institut Heidelb.
No. 32 (Catalog I/149)
(End) Yuri Kolesnik [Inst. Astronomy Moscow] 1997-Mar-28