AGK3R I/161 (Smith 1990)
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AGK3R
Smith Jr. C.A.
<unpublished, (1990)>
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ADC_Keywords: Positional data ; Proper motions
Abstract:
A catalog of positions of reference stars distributed uniformly on the
celestial sphere north of declination -5 deg. contains meridian
observations of 21,499 stars with a mean epoch 1958.5. This catalog was
compiled from more than 300,000 observations made with 11 northern
meridian circles during the period 1956 to 1963. The observations are on
the FK4 system.
Introduction:
There is a need for reference catalogs with good modern positions.
Recently, positions were redetermined for Northern Hemisphere reference
stars to form the AGK3R catalog that was used to determine the plate
constants for the AGK3 Photographic Catalog (Dieckvoss 1975). The AGK3R
catalog contains 21,499 stars evenly distributed on the surface of the
celestial sphere from -5 deg. to +90 deg. The observations were made
with 11 northern meridian circles during the period 1956 to 1963. Stars
were selected from two lists: one selected at the U. S. Naval
Observatory and the other at the Pulkovo Observatory and the Sternberg
Institute. The participating observatories were Bergedorf, Bordeaux,
Greenwich, Heidelberg, Nicolaev, Ottawa, Paris, Pulkovo, Strasbourg, and
the U. S. Naval Observatory (Smith, 1980). Both the seven-inch and the
six-inch transit circles were employed at the U. S. Naval Observatory.
All observations were reduced on a nightly basis by the observers to the
FK3R system and, later to the FK4 either by the observer himself or at
the U.S. Naval Observatory.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
data.dat 72 21499 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- 5 I5 --- ID *AGK3R number
6 A1 --- lcode *List code
7- 11 I5 --- ob_id AGK3R number in the observing list
12- 14 I3 --- DMz ?BD Zone
15- 19 I5 --- DMno *?BD number
20- 22 F3.1 mag mag Magnitude
23- 24 A2 --- Sp *Spectral type
25- 26 I2 h RAh Right ascension, hours (1950)
27- 28 I2 min RAm Right ascension, minutes (1950)
29- 34 F6.3 s RAs Right ascension, seconds (1950)
35- 41 F7.4 s e_RAs Mean error of RA reduced to equator
42- 43 I2 --- o_RAs No. observations in right ascension
44- 49 F6.3 ma Ep_RA Epoch of right ascension - 1900.000
50 A1 --- DE- Declination sign (1950)
51- 52 I2 deg DEd Declination, degrees (1950)
53- 54 I2 arcmin DEm Declination, minutes (1950)
55- 59 F5.2 arcsec DEs Declination, seconds (1950)
60- 64 F5.2 arcsec e_DEs Mean error of declination.
65- 66 I2 --- o_DEs No. Observations in declination.
67- 72 F6.3 ma Ep_DE Epoch of declination. - 1900.000
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Note on ID:
Four stars appeared twice in the original AGK3R observing list under
different serial numbers. The data from the duplicate stars have been
combined and the stars renumbered (AGK3R numbers). The duplicate stars
removed and the number assigned in the new numbering system are as
follows:
Current AGK3R Number Duplicate AGK3R Numbers
in Observing List
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1930C 1932
1931, 2405C 2407, 2408
2951C 2954, 2955
3633C 3637, 3638
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Note on lcode:
S = U. S. Naval Observatory List
Z = Pulkovo Observatory and Sternberg Institute List
C = Both lists
Note on DMno:
The only star without a DM number is 1135Z. It was formerly listed as
BD-01 deg.170A but has no connection with BD-01 deg.170.
Note on Sp:
An & in byte 23 indicates that the spectrum is composite. The types for
these stars are as follows:
AGK3R Number Spectral Types
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4536C A + G
4996S F8 + A0
5217S A0 + G0
5739S F0 + A2
6063S F5 + A5
6123S F5 + A3
6324S F5 + A
6754S A2 + G
7251S F2 + A2
8698S F2 + A2
10048S F5 + A5
11154S F5 + A3
12871S F5 + A0
13650S A2 + G
16982S A0 + G
17619S K0 + A0
17641S F5 + B8p
18095S G0 + A
18453S F5 + A3
18727S K0 + A2
19812S G5
20257S A3 + G
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Remarks and Modifications:
Changes in the catalog as received from the U.S. Naval Observatory have
been minor. The false DM number was removed for 1135Z and several bytes
were changed to make their meaning more obvious to the user. Bytes 66 -
80 were dropped. In the version received, bytes 66 - 75 were blank and
bytes 66 - 80 contained only the second numbers for the stars that had
duplicate entries . The spectral types for the stars with composite
spectra were obtained from the Henry Draper Catalogue or the
Transactions of the Yale University Observatory v.25.
We thank Clayton A. Smith for assistance with the preparation of this
document.
References:
"Bonner Sternverzeichnis, 1.", Argelander, Friedrich Wilhelm August 1859,
Bonn : Adolf Marens, 1859; 1 v. ; in 4.; XI.4.6=1859bost.book.....A
"Bonner Sternverzeichnis, 2.", Argelander, Friedrich Wilhelm August 1860,
Bonn : Adolf Marens, 1860; 1 v. ; in 4.; XI.4.6=1860bost.book.....A
"Bonner Sternverzeichnis, 3.", Argelander, Friedrich Wilhelm August 1862,
Bonn : Adolf Marens, 1862; 1 v. ;...