V/77 Skymap Star Catalog - Version 3.7 (Slater+ 1992)

Skymap, Revision 3 - Update 1 (version 3.7)

Slater M., and Hashmall J.

<NASA/Goddard Space Flight Center Document 554-FDD-89/001R3UD1 (1992)>

Abstract:

The SKYMAP system was developed to provide an accurate and complete catalog of all stars with blue or visual magnitudes brighter than 9.0 for use by attitude determination programs. The catalog contains approximately 248560 stars. Because for this use, completeness is more important than high accuracy, many quantities are little more than good guesses. The catalog contains data for the following four purposes:

1. Cross-referencing stars to other catalogs
2. Calculating star instrumental magnitudes
3. Calculating star positions at a given epoch
4. Determining star position errors, distances to near neighbors, and magnitude variability.

Introduction:

The original version has been improved and updated with corrections several times. Version 3.7 incorporates known errors documented previously in SKYMAP Error Reports. Magnitude errors discovered in SKYMAP Version 3.6 were corrected. Other minor catalog corrections, including the deletion of five duplicate entries and the addition of two stars, were also performed. The original catalog was compiled by D. M. Gottlieb of Computer Sciences Corporation (CSC) under contract to NASA. The compilation and statistics of the catalog are described by Gottlieb (1978), while the source referenced above describes in detail the contents of the current version and the derivation of values not available observationally.

* IMPORTANT NOTE: THIS CATALOG WAS NOT COMPILED TO PROVIDE THE MOST ACCURATE AND RELIABLE DATA AT THE ASTRONOMICAL RESEARCH LEVEL. THE DERIVATIONS OF TWO-DIMENSIONAL MK TYPES FROM ONE-DIMENSIONAL DATA, UBV VALUES FROM PHOTOVISUAL AND PHOTOGRAPHIC MAGNITUDES, AND STELLAR DISTANCES FROM MAGNITUDES AND SPECTRAL TYPES ARE EXTREMELY UNCERTAIN, SO THESE DATA SHOULD NOT BE USED WITHOUT CAREFUL SCRUTINY. THE VARIOUS FLAGS ASSOCIATED WITH CATALOG DATA SHOULD BE RETAINED WITH THE DATA AT ALL TIMES OR GROSS MISINTERPRETATIONS MAY RESULT. USERS OF THIS CATALOG SHOULD KEEP THESE FACTS IN MIND CONSTANTLY.

File Summary:

Byte-by-byte description of file: skymap.dat

Note on SKM:

An internal number in the form xxyyzzzz, where xx and yy are hours and minutes of right ascension for the standard equinox and epoch 2000.0 and zzzz is a running sequential index for all stars having the same xx and yy.

Note on DM*:

The DM number consists of a zone number referring to the declination of the star at the epoch of the DM (1855.0 for stars north of declination -22 deg.; 1875.0 for stars south of declination -21 deg.) and a sequential number in that zone. For ease of computation, these numbers have been converted into a single integer, defined as follows:

D = 100000*(Z+100) + N for Z positive

D = 100000*(Z+99) + N for Z negative

where D = converted DM number, as given in this catalog

Z = the declination zone number

N = the sequential number in the zone

Note on GCVS:

A sequential record number from The General Catalogue of Variable Stars (GCVS) (Kukarkin et al. 1969-70). This number originally defined in alphabetical order of constellation and bears no relation to a star's position. It is not a useful number for external applications.

Note on name:

Greek letters are represented by three-letter abbreviations, as are constellation names.

Note on RA and DE:

Preferentially from the SAO Catalog. Lacking SAO data, the data are taken, in order of preference, from: Astronomiches Rechen Institute (ARI) (1975), Blanco et al. (1968), Kukarkin et al. (1968), United States Naval Observatory (USNO) (1974-75), Cannon and Pickering (19198-24) and Cannon and Mayall (1949).

Note on e_pos:

Taken from the SAO when available. The error is set to 0.5" for AGK3 stars, 35" for HD(E) stars, and 100" for all others except some selected cases for which the value is 180". The reported value is the total error, which is the sq.rt.(2) times the sum of the errors in RA and DE. The errors in RA and DE are approximately equal.

Note on giu_*:

Geocentric Inertial (G.I.) unit vector with the components:

(X; Y; Z) = (cos(DE)*cos(RA); cos(DE)*sin(RA); sin(DE)

where (X, Y, Z) is the respective unit vector.

Note on RA-50 and DE_50:

Taken, in order of preference, from the SAO, the AGK3 Star Catalogue of Positions and Proper Motions North of -2.5 deg Declination (Dieckvoss 1975), Blanco et al. (1968), Jaschek (1978), and Worley (1976).

Note on motRA and motDE:

Where there is no proper motion, this value is for precession only.

Note on n_U:

The meaning of each value is given below:

0: no U magnitude provided

1: U magnitude observed

2: U magnitude computed according to procedure given by Slater and Hashmall (1992)

3: U-B observed and B computed from photovisual and/or photographic magnitudes

Note on B and V:

When observed values of B and V were not available, they were derived from color index or photographic and/or photovisual magnitudes according to the procedure given by Slater and Hashmall (1992).

Note on n_BV:

This flag gives the method by which the best values of the B and V magnitudes were obtained. The meaning of each value is given below:

1: observed, taken from Nicolet (1978) or Blanco et al. (1968).

2: observed, taken from the Index Catalogue of Visual Double Stars (Worley 1976)

3: converted from the HD or SAO photographic (ptg) and photovisual (ptv) magnitudes, using eq. (3-8) given by Slater and Hashmall (1992)

4: converted from the HD or SAO, photographic (ptg) and photovisual (ptv) magnitudes, using eq. (3-9) given by Slater and Hashmall (1992)

5: converted from the HD or SAO photographic (ptg) and photovisual (ptv) magnitudes, using eq. (3-10) given by Slater and Hashmall (1992)

6: unconverted HD (V=ptv, B=ptg) reported because spectral class unavailable

7: same as above, when only V = ptv available

8: same as above, when only B = ptg available

9: B from the AGK3 and V from spectral type if available

10: V observed from Blanco et al. (1968) or Mermilliod & Nicolet (1977), and B obtained from Eq. (3-9) given by Slater and Hashmall (1992)

11: (B-V) color inferred from (ptg-ptv) and observed V. Estimated 1 standard deviation error is 0.4 magnitudes in B and 0.2 in V. Affects about 600 SKYMAP stars

12: similar to previous value (11), V observed, only one of ptv or ptg available, and no spectral data. Magnitude uncertainty estimated at 0.2 in V and 0.3 in B.

Note on mpv and mpg:

Ptv and ptg were obtained from the HD or the SAO (for non-HD stars). They correspond approximately to V and B, respectively, but no spectral response curves are available for them.

Note on n_p:

0: neither ptv nor ptg available

1: both ptv and ptg available from observations

2: ptv available from observations and ptg derived from ptv and spectral type

3: ptg available from observations and ptv derived from ptg and spectral type

4: ptv available from observations; ptg not given

5: ptg available from observations; ptv not given

Note on sp:

The numerical code equivalents of the spectral classes are as follows:

The first two digits give the letter code:

00: O 07: R

01: B 08: N

02: A 09: C

03: F 10: S

04: G 11: WR

05: K 12: WC

06: M 13: WN

The third digit is the number following the spectral type letter code; e.g., A8 becomes 02800.

The fourth digit is 0 except for some O and M stars, and for stars with fractional spectral types (typically in 0.5 increments). For O and M stars with small letters following the spectral type letter or number (e.g., O8f or Ma), the coding is:

1: a 6: d

3: b 7: e

4: c 9: f

For stars with a fractional spectral type, the fraction is encoded in the fourth digit. For example, B1.5 becomes 01150.

The fifth digit implies precision of the source of the spectral type as:

0: precise, or not given

1: one or less than one subclass uncertainty

2: two subclasses of uncertainty

3: three subclasses of uncertainty

4: four subclasses of uncertainty

5: five or more subclasses of uncertainty

6: old style spectral class

7: no subclass

8: - probably earlier spectral class than shown

9: + probably later spectral class than shown

A few special codes appear, which are as follows:

00000 no spectral class available

99999 peculiar

99998 nova-like spectrum

Note on Lum:

The codes for luminosity class are as follows:

5: 0 30: III

9: Ia+ 31: IIb-IIIa

10: I 32: IIIa

11: Ia-0 34: IIIab

12: Ia 35: III-IV

13: Ia-Iab 38: IIIb

14: Iab 40: IV

15: I-II 42: IVa

16: Ia-Ib 44: IVab

17: Iab-Ib 45: IV-V

18: Ib 48: IVb

19: Ib-II 50: V

20: II 52: Va

21: Ib-IIa 54: Vab

22: IIa 55: V-VI

23: IIa-IIab 58: Vb

24: IIab 60: VI subdwarfs

25: II-III 70: VII white dwarfs

26: IIa-IIb -10: c pre-MK class

27: IIab-IIb -30: d pre-MK class

28: IIb -50: g pre-MK class

29: IIb-III

Intermediate classes are averaged; e.g., III-IV becomes 35.

Note on pec:

The code is a 6-digit integer of the form AABBCC. The AA group indicates general stellar peculiarities, the BB group gives chemical abundance peculiarities and the CC group gives peculiarities in characteristics of line strengths.

The AA subcode consists of 0 to 2 digits as follows: (Codes in parentheses are SKYMAP abbreviations, bytes 267-268).

1: metallic-line star (MT)*

2: composite spectrum for multiple star (CO)

3: shell star (SH)

4: variable spectrum (VR)

5: star + nebular (NB)

6: dwarf cepheid variable (DC)

The BB subcodes are: (Codes in parentheses are SKYMAP abbreviations, bytes 269-270).

Strontium stars:		Barium stars:
01: (SR)		50: (BA)
02: (SR, EU)		51: (BA-O)
03: (SR, SI)		53: (BA-II
04: (SR, CR)		Miscellaneous
05: (SR, SI, EU)		60: (WK1)
06: (SR, SI, CR)		61: (CH)
07: (SR, SI, HG)		62: (CA 0.)
08: (SR, CR, HG)		63: (CA 1)
Silicon stars:		Cyanogen strength:
10: (SI)		70: (CN-1)
11: (SI, CR)		71: (CN+1)
12: (SI, CR, FE)		72: (CN-2)
13: (SI, EU)		73: (CN+2)
14: (SI, MG)		74: (CN-3)
15: (SI, EU, HG)		76: (CN1)
17: (SI, 4200)		81: (CNIA)
Single element peculiarities:		98: (CNI5)
18: (SI, FE)		83: (CNIA/B)
19: (SI, 3955)		84: (CNIB)
Mercury stars:		85: (CNIB/II)
21: (HG)		86: (CN II)
22: (HG, MN)		87: (CN II/III)
23: (HG, MG, EU)		88: (CN III)
24 : (HG, SI)		89: (CN III/IV)
Chromium stars:		90: (CN IV)
31: (CR)		91: (CN IV/V)
32: (CR, EU)		92: (CN V)
33: (CR, SR, EU)		95: (CN+2, Wk1)
34: (CR, SI, EU)		96: (CN-1, Wk1)
35: (CR, SI, 4200)		97: (CN5)
Single element peculiarities:		98: (CNI5)
41: (He)
42: (EU)
43: (MN)
44: (H)
45: (4200)
46: (4078)

The symbols shown above are chemical elements whose spectral lines are anomalously intense, or individual wavelengths that are intense. Observers usually list the elements in order of abundance; however, SKYMAP ignores such ordering for the purpose of simplification. The symbol CN is followed by an index running from +3 to -3, and an MK luminosity class. The index implies CN bands running from much stronger than normal to barely perceptible.

The CC digits are: (Codes in parentheses are SKYMAP abbreviations, bytes 217-272).

01: peculiar (p)

02: rapid rotator (N)

03: codes 01 & 02 (NP)

04: emission lines (E)

05: codes 01 & 04 (PE)

06: codes 02 & 04 (NE)

07: codes 01, 02, and 04 (NPE)

10: weak lined star (WL)

11: codes 01 & 10 (WL,P)

14: codes 04 & 10 (WL,E)

20: very rapid rotator (NN)

21: codes 01 & 20 (NN,P)

24: codes 04 & 20 (NN,E)

25: codes 01, 04, & 20 (NN,PE)

30: strong or sharp line (ST)

31: codes 01 & 30 (ST P)

33: codes 01, 02, & 30 (ST PN)

40: very strong lines (VS)

50: very week lines (VW)

08: Wolf-Rayet subtypes (-A)

09: special case of code 08 (-B)

18: weak emission in O stars (F)

28: emission in O stars ((F))

38: strong emission in O stars ((F)))

48: very strong emission in O stars (F, PE)

19: OB stars in Walborn System ((N))

39: OB stars in Walborn System (((N)))

96: codes 20 & 97 (NN, K)

97: presence of Interstellar lines (K)

98: broad and sharp line (NS)

99: typical peculiarities (PEC)

-1: extreme shell star (Eq)

-2: horizontal branch star (HB)

-3: central star of Planetary Nebula (PLAN)

Note on sp, Lum, and pec:

Examples of converted Sp. types:

		Data		Coded as:
Sp. class		G9		4900
		WN6		13600
		O8.5		850
Lum. class		V		50
		I-II		15
Peculiarity		p Si Eu		1301
		CO		20000
		((n))		39

Note on n_sp:

This variable specifies the source for the spectral class, luminosity class, and peculiarity code.

0: Spectral class, luminosity class, and peculiarity code not available.

1,2,3: Spectral class, luminosity class, and peculiarity code observed in the MK system and reported by Jaschek (1978), Mermilliod (1973), or Blanco et al. (1968), respectively.

4: Spectral class observed in the HD system and converted to spectral class and luminosity class in the MK system; the peculiarity code was set to 0.

5: Same as 4 for SAO spectral types.

6: Same as 4 for AGK3 spectral types.

7: Spectral class, luminosity class, and peculiarity code reported by Houk & Cowley (1975), and Houk (1978,1982).

Note on sp_HD:

The spectral type in the HD system as given in the HD and the SAO consists of a spectral class only. The spectral class code is 4-digit integer. The first two digits are the same as those for the spectral class, best value (bytes 259-263). The third digit is the number following the spectral type letter code; e.g., A8 becomes 0280. If no spectral-type number is given the third and fourth digits are 7. For example, A becomes 0277. The fourth digit is 0 except for the old style of spectral class for some O and M stars, and for stars with fractional spectral types. For O and M stars with small letters following the spectral type letter or number (e.g., O8f or Ma), the coding is:

1: a		4: d
2: b		6: e
3: c		8: f

Note on MK_cl:

Obtained from Jaschek (1978) or if not available there, from Blanco et al. (1968). The numerical codes are the same as the codes of the spectral class, best value (bytes 259-263).

Note on MK_lum:

Numerical codes are the same as the codes of the luminosity class, best value (bytes 264-266).

Note on MK_pec:

Numerical codes are the same as the peculiarity code, best value (bytes 267-272).

Note on n_MK:

MK spectral type source flag, as defined below:

0: none available

1: taken from Jaschek (1978)

2: taken from Mermilliod (1973)

3: taken from Blanco et al. (1968)

Note on M:

The calibration is taken from Keenan (1963), except for supergaints, which is taken from Blaauw (1963).

Note on RV:

Observed radial velocities are from the General Catalogue of Stellar Radial Velocities (GCRV) (Wilson 1953). For stars not in the GCRV, the inverse of Sun's motion relative to the local standard of rest (LSR) in the direction of the star is taken as the radial velocity. This is statistically the most likely value.

Note on dist:

If trigonometric parallax and spectroscopic distances are both available, they are combined to yield the best distance. If only one distance is available, it is used. The detailed procedure is described by Slater and Hashmall (1992).

Note on n_dist:

The meanings are:

0: no distance given

1: distance obtained from trigonometric parallax alone

2: distance obtained from spectroscopic parallax alone

3: distance obtained is a combination of trigonometric and spectroscopic parallaxes

4: distance cited is a minimum distance computed from trigonometric parallax.

5: distance cited is a maximum distance computed from space velocities.

Note on n_AV:

This flag indicates which method was used to obtain interstellar absorption:

0: no absorption given

1: absorption derived from B and V magnitudes alone

2: absorption derived from U, B, and V magnitudes

3: absorption derived from distance and direction to the star

Note on u_var:

If the variability of a star is considered questionable, this flag is 1; otherwise, it is 0.

Note on var_mty:

If this flag has a value of 1, m refers to B or ptg; if it is 2, the difference refers to V.

Note on var_ep:

The epoch of the variable star is the time of a reference point in its light variation function, usually the time of minimum light. It is expressed in Julian days minus 2,400,000. Kukarkin and Parenago (1963) may be consulted for more detailed information.

Note on yr_obs:

The year in which the separation observation was made can be used to determine the validity of the assumption that the separation is still valid.

Note on del_*:

If the distance is more than 0.5 degree, it is coded as 360.0. If the nearest neighbor is a member of a physical multiple star system with this star, it is made negative (hence -0.01 means that the nearest star to this star is 0.01 degree away and is part of a multiple star system.

Note on r_pos_cd:

This flag gives the source of the star's position:

1: SAO Star Catalog (SAO Staff 1966).

2: The HD Catalogue (Cannon and Pickering 1918-1924) and The HD Extension (Cannon 1925-1936, Cannon and Walton Mayall 1949).

3: Photoelectric Catalogue (Blanco et al. 1968).

4: Catalogue of Selected Spectral Types in the Morgan-Keenan System (Jaschek 1978).

5: Index Catalogue of Visual Double Stars (Worley 1976).

6: General Catalogue of Trigono- metric Stellar Parallaxes (Jenkins 1952).

7: General Catalogue of Stellar Radial Velocities (Wilson 1953).

8: AGK3 Star Catalogue of Positions and Proper Motions North of -2.5 Deg Declination (Dieckvoss 1975).

9: General Catalogue of Variable Stars (Kukarkin et al. 1969- 1970).

10: Miscellaneous.

Note on r_RV:

This flag gives the source of the star's radial velocity. If it is 0, the radial velocity quoted is the inverse of the Sun's motion; if it is 1, the redial velocity is taken from General Catalogue of Stellar Radial Velocities (Wilson 1953).

Note on n_mult:

This flag gives the source of multiple-star data:

0: No multiple-star data given

1: Index Catalogue of Visual Double Stars (Worley 1976).

2 - 23599999: Two or more source-catalog stars within 1' of one another were combined. This gives the SKYMAP number of the secondary.

99999999: Two or more source-catalog stars within 1' of one another were combined. The secondary had no HD number.

Note on E_RA and E_DE:

The systematic errors in R.A. and Dec. are for HD stars in the region of the sky including this star. The correction must be added to the HD position to correct the systematic errors. These errors are valid only for stars whose positions come from the HD or HDE. Additional details can be found in Gottlieb (1977).

Note on r_pos:

The source of the position at the standard epoch is encoded as follows:

SAO:		SAO Star Catalog (SAO Staff 1966).
HD:		The HD Catalogue (Cannon and Pickering 1918-1924) and The HD Extension (Cannon 1925-1936, Cannon and Walton Mayall 1949).
BLAN:		Blanco et al. (1968).
JAS:		Catalogue of Selected Spectral Types in the Morgan-Keenan System (Jaschek 1978).
MULT:		Index Catalogue of Visual Double Stars (Worley 1976).
PAR:		General Catalogue of Trigono- metric Stellar Parallaxes (Jenkins 1952).
WIL:		General Catalogue of Stellar Radial Velocities (Wilson 1953).
AGK3:		AGK3 Star Catalogue of Positions and Proper Motions North of -2.5 Deg Declination (Dieckvoss 1975).
VAR:		General Catalogue of Variable Stars (Kukarkin et al. 1969-1970).

Note on r_U:

Blank U magnitude observed on the UBV system or none given in U magnitude, best value (bytes 207-212). * U magnitude computed as noted under U magnitude derivation flag.

Note on r_BV:

Blank V and B both observed.

C converted from HD or SAO magnitudes as noted in V and B magnitudes derivation flag (bytes 226-227)

H unconverted from HD or SAO magnitudes

* V observed in UBV system; B computed from V and the spectral type or not given in B magnitude, best value (bytes 214-219)

Note on pec_cd:

There is an asterisk (*) between each group.

Note on r_sp:

Blank observed on the MK system or not given H converted from the HD system

Note on r_d:

The method by which the best distance (bytes 383-389) was derived is encoded as follows:

Blank		no distance given
T		distance from trigonometric parallax (!t)
S		distance from spectroscopic parallax (!sp)
S,T		distance from a combination of !t and !sp
MIN		distance is a minimum distance from !t
MAX		distance is a maximum distance from space velocities

Note on r_AV:

The source of the interstellar absorption A(V) (bytes 408-413) is encoded as follows:

BV	:	derived from B and V
UBV	:	derived from U, B and V
*	:	derived from distance and direction

Note on var_ty:

An 8-character description of the type of variabilty is given. (See table 2)

Note on mp:

The values for this flag are:

0: No ptv or ptg data

1: HD catalog source

2: SAO catalog source

3: AGK catalog source

Table 1

Variable Star Codes:

* "late" spectral type refers to relatively cool stars (spectral types K,M,N,R,S,C).

Remarks:

The tape version of the SKYMAP Catalog of 248516 Stars, Version 3.3 was received from Code 554, NASA/Goddard Space Flight Center, on September 17, 1986. It contained logical records consisting of a combination of binary and EBCDIC data. To facilitate wider use of all SKYMAP data without the necessity for translating the binary data by other than IBM-compatible computer systems, a formatted (character) version was prepared at the ADC. The word numbers of 96 through 106, 119, and 120 which are redundant character data for the purpose of printing were eliminated and all binary data were converted to character form in the version of the catalog which is described in this document.

References:

Aitken, R. G. 1932, New General Catalogue of Double Stars within 120 deg. of the North Pole, Carnegie Institution of Washington Pub. 417 (Washington: Carnegie Institution of Washington).

Argelander, F. 1859-1862, Bonner Sternverzeichnis, Erste bis dritte sektion, Astronomischen Beobachtungen auf der Sternwarte der Koeniglichen Rhein. Friedrich-Wilhelms-Universitaet zu Bonn, Bands 3-5.

Blaauw, A. 1963, Basic Astronomical Data, ed. K. Aa. Strand (Chicago: University of Chicago Press), p. 383.

Blanco, V. M., Demers, S., Douglass, G. G., and FitzGerald, M. P. 1968, Photo electric Catalogue, Pub. U.S. Naval Obs., 2nd Ser., 21.

Cannon, A.J. 1925-1936, The Henry Draper Extension, Ann. Astron. Obs. Harvard College 100.

Cannon, A. J. and Pickering, E. C. 1918-1924, The Henry Draper Catalogue, Ann Astron. Obs. Harvard College 91-99.

Cannon, A. J. and Walton Mayall, M. 1949, The Henry Draper Extension, The Ann J. Cannon Memorial Volume, Ann. Astron. Obs. Harvard College 112.

Dieckvoss, W. (in collaboration with H. Kox, A. Gunther and E. Brosterhus) 1975, AGK3 Star Catalogue of Positions and Proper Motions North of -2.5 Deg Declination, Hamburg-Bergedorf (printed with financial support from Deutsche Forschungsgemeinschaft Bonn-Bad Godesberg).

Gill, D. and Kapteyn, J. C. 1896 -1900, Cape Photographic Durchmusterung, Ann Cape Obs. 3-5.

Gottlieb, D. M. 1977, The Accuracy of SKYMAP Star Positions, Computer Science Corporation, CSC/TM-77/6009.

Gottlieb, D. M. 1978, SKYMAP: A New Catalog of Stellar Data, Astrophys. J. Suppl. 38, 287.

Gottlieb, D. M. 1979a, SKYMAP System Description: Star Catalog Data Base Generation and Utilization, Computer Sciences Corporation, CSC/SD-76/6041UD

Gottlieb, D. M. 1979b, Comparison of SKYMAP and Nicolet Star Magnitudes, Computer Sciences Corporation, CSC/TM-79/6172.

Hoffleit, D. (with the collaboration of Jaschek, C.) 1982, The BRIGHT STAR CATALOGUE, 4th revised edition (New Haven: Yale University Observatory).

Houk, N. 1978, The Michigan Catalogue of Two-Dimensional Spectral Types for the HD Stars, Zones -52 deg to -40 deg, V. 2 (Ann Arbor: University of Michigan).

Houk, N. 1982, The Michigan Catalogue of Two-Dimensional Spectral Types for the HD Stars, Zones -40 deg to -26 deg, V. 3 (Ann Arbor: University of Michigan).

Houk, N. and Cowley, A. 1975, The Michigan Catalogue of Two-Dimensional Spectral Types for the HD Stars, Zones -89 deg to -53 deg, V. 1 (Ann Arbor: University of Michigan).

Jaschek, M. 1978, Catalogue of Selected Spectral Types in the Morgan-Keenan System, Bull. Inf. Centre Donnees Stellaires No. 15, 121.

Jenkins, L. F. 1952, General Catalogue of Trigonometric Stellar Parallaxes, (New Haven: Yale University Observatory).

Johnson, H. L. and Morgan W. W. 1953, Astrophys. J., 117, 313.

Keenan, P. C. 1963, Basic Astronomical Data, ed. K. Aa. Strand. (Chicago: University of Chicago Press), p. 78.

Kuestner, F. 1903, Bonner Durchmusterung des Noerdlichen Himmels, zweite berichtigte Auflage, Bonn Universitaets Sternwarte (Bonn: A. Marcus und E. Weber's Verlag).

Kukarkin, B. V., Kholopov, P. N., Pskovsky, Yu. P., Efremov, Yu. N., Kukarkina, N. P., Kurochkin, N. E., Medvedeva, G. I., Perova, N. B., Fedorovich, V. P. and Frolov, M. S. 1969-70, General Catalogue of Variable Stars, 3rd edition (Moscow: Publishing House of the Academy of Sciences of the U.S.S.R.).

Kukarkin B. V. and Parenago, P. P. 1963, Basic Astronomical Data, ed. K. Aa. Strand (Chicago: University of Chicago Press), p. 328.

McLaughlin, S. F. 1980a, SKYMAP System User's Guide, Computer Sciences Corporation, CSC/SD-80/6035.

McLaughlin, S. F. 1980b, SKYMAP System Description: Star Catalog Data Base Generation and Utilization, Section 4 only (revised August 1980).

Mihalas, D. 1968, Galactic Astronomy (San Francisco: W. H. Freeman Company).

Mermilliod, J.-Cl. 1973, A New Catalogue of Stellar UBV Photoelectric Photometry II, Bull. Inf. Centre Donnees Stellaires No. 4, 20.

Mermilliod, J. C. and Nicolet, B. 1977, Astron. Astrophys. Suppl. 29, 259.

Morgan W. W., Keenan, P. C. and Kellman, E. 1953, An Atlas of Stellar Spectra (Chicago: University of Chicago Press).

Nicolet, B. 1978, Astron. Astrophys. Suppl. 34, 1.

Schoenfeld, E. 1886, Bonner Sternverzeichnis, Vierte Sektion, Astronomische Beobachtungen auf der Sternwarte der Koeniglichen Rheinischen Friedrich- Wilhelms-Universitat zu Bonn 8, Part IV (Bonn: Adolph Marcus).

Smithsonian Astrophysical Observatory Staff 1966, Star Catalog. Positions an Proper Motions of 258,997 Stars for the Epoch and Equinox of 1950.0, Pub. o the Smithsonian Institution of Washington, D. C. No. 4652 (Washington: Smithsonian Institution).

Standish, E. M. 1982, Astron. Astrophys. 115, 20.

Thome, J. M. 1892-1932, Cordoba Durchmusterung, Resultados del Observatorio Nacional Argentino 16 (1892, Part I: -22 deg to -32 deg), 17 (1894, Part II: -32 deg to -42 deg), 18 (1900, Part III: -42 deg to -52 deg), 21 (Part I) (1914, Part IV, -52 deg to -62 deg), 21 (Part II) (1932, Part V: -62 deg to -90 deg).

Wilson, R. E. 1953, General Catalogue of Stellar Radial Velocities, (Washington: Carnegie Institution of Washington).

Worley, C. E. 1976, Index Catalogue of Visual Double Stars, 1976.5 updated magnetic tape version (Washington: U. S. Naval Observatory).

(End) Nancy G. Roman [ADC/SSDOO] Sep-6-95