catalogues and names

The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version)

SKY2000 - Master Star Catalog

Smithsonian Astrophysical Observatory Star Catalog

The Washington Visual Double Star Catalog, 1996.0

Combined General Catalogue of Variable Stars (Vol. I-III)

catalogues and names

catalogues and names	m Sgr, mu Sgr, 13 Sgr, HR 6812, HD 166937, SAO 186497, BD -21 4908, FK5: 682, WDS 18138-2104A
constellation	Sagittarius

data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)

position, motion, parallax:

position (J2000)	RA: 18h 13min 45.8sec	DEC: -21° 3' 32''
position (2000.73)	RA: 18h 13min 49sec	DEC: -21° 3' 31''
position (B1900)	RA: 18h 7min 46.9sec	DEC: -21° 5' 6''
proper motion (J2000)	RA: 0.002 arcsec/a	DEC: 0.001 arcsec/a
radial velocity	-6 km/s note: spectroscopic binaries note: orbital data avaible
rotational velocity	=<54 km/s (uncertain) (variable)
trigonometric parallax	0.012 arcsec
galactic coordinates	longitude: 10°	latitude: -1.6°

magnitude

visual magnitude

3.86 (V on UBV Johnson system)

spectral / color information

spectral class	B8Iap
B-V-magnitude	0.23
U-B-magnitude	-0.49
R-I-magnitude

note (category: spectra):

Shell star.

variability information

variable star identification

Mu Sgr

note (category: variability):

ADS 11169A, EA 3.79 - 3.92V, 180.45d. Also irregular changes in brightness.

double/multiple star system information

number of components of multiple star system	6
separation	0 arcsec
mag difference (of double or brightest multiple)	2.9

note (category: double and multiple data):

ADS 11169A is SB, 4.1, 7.0v, sep. 0.011". Closest visual companion is B, 11.5v, B9III at 17"; C is 13.5v at 26"; D, 9.9v, B3; E, 9.4v, B2V, physical, vsini 184k/s.

note (category: spectroscopic binaries):

ADS 11169A, 180.45d, K 56.8k/s, V0 -2.7k/s, asini 129.

miscellaneous information

note (category: group membership):

Sgr OB1.

data from SKY2000 - Master Star Catalog (Myers+ 1997)

position, motion, parallax:

position (J2000)	RA: 18h 13min 45.812sec	DEC: -21° 3' 31.79''	±0.06 arcsec	source: 15
position (2000.73)	RA: 18h 13min 49sec	DEC: -21° 3' 31''	JD: 2451810.11
proper motion (J2000)	RA: 0.0001 arcsec/a	DEC: 0.001 arcsec/a		source: 25
radial velocity	-6 km/s			source: 25
trigonometric parallax	0.012 arcsec		±0.001 arcsec	source: 25
galactic coord. (B1950)	longitude: 10.01°	latitude: -1.6°

magnitude:

visual	3.8 (observed)	source: 30
photovisual	4	source: 2
photographic	4	source: 2

spectral information:

spectral class	B8		source: 96
Morgan-Keenan	B8Iap		source: 25
B-magnitude	4.09 ±0.05	B-V-magnitude	0.23
U-magnitude	3.6 ±0.05	U-B-magnitude	-0.49

variability information:

source of data: 30

variability type	10
var. amplitude	0.08
var. period	180.55
var. epoch	2444035 10. June 1979, 12:00:00 UT
next max light	2451979.2 10. March 2001, 16:48:00 UT

double/multiple star system information:

source of data: 19

separation between brightest and second brightest component	16.9 arcsec
magnitude difference between brightest and second brightest component	6.63
position angle	258 °

sources:

2	HD and HDE Catalogs
Cannon, A.J., and E.C. Pickering, Harvard Annals, Vols 91-99, 1918-24, Cambridge, Massachusetts: Harvard University; Cannon, A.J., Harvard Annals, Vol. 100, 1925-36, Cambridge, Massachusetts: Harvard University; and Cannon, A.J., and M. Walton Mayall, Harvard Annals, Vol. 112, 1949, Cambridge, Massachusetts: Harvard University
15	FK5, FK5 Extension and FK5 Supplement
Fricke, W., H. Schwan and T. Lederle, "Fifth Fundamental Catalogue (FK5), Part I. The Basic Fundamental Stars," Veroff. Astronomisches Recheninstitut, No. 32, Heidelberg, Germany, 1988, and Fricke, W., H. Schwan, and T.E. Corbin, "Fifth Fundamental Catalogue (FK5), Part II. The FK5 Extension," Veröff. Astronomisches Recheninstitut, No. 33, Heidelberg, Germany, 1991
19	WDS Catalog
Worley, C.E., and G.G. Douglass, Washington Catalog of Visual Double Stars 1996.0, United States Naval Observatory, 1996
25	Bright Star Catalogue, 5th edition
Hoffleit, D. and Warren, W.H. Jr., The Bright Star Catalogue, 5th Revised Edition, Version 2, 1994
30	GCVS, 4th edition
Kholopov, P.N., et al., General Catalogue of Variable Stars, fourth edition, Moscow: Nauka Publishing House, 1985-88
96	SAO or HD/HDE Catalog
Reference from Value 1 or Reference from Value 2

data from Smithsonian Astrophysical Observatory Star Catalog (SAO Staff 1966; USNO, ADC 1990)

position and proper motion:

position (B1950)	RA: 18h 10min 46.324sec	DEC: -21° 4' 25.46''	±0.004 arcsec
position (2000.73)	RA: 18h 13min 48sec	DEC: -21° 3' 31''	JD: 2451810.11
position (J2000)	RA: 18h 13min 45.822sec	DEC: -21° 3' 31.75''
proper motion B1950 (FK4)	RA: 0.0002 arcsec/a	DEC: 0.001 arcsec/a	±0.001 arcsec/a in RA ±0.001 arcsec/a in DEC
proper motion J2000 (FK5)	RA: 0.0002 arcsec/a	DEC: 0.002 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	4 (accuracy: 2 decimals)
source of visual magnitude data	Taken from the "Henry Draper Catalogue".

spectral information:

spectral class	B8p
source of spectral data	Taken from the Henry Draper Catalogue or no spectrum in source catalog.

catalogues

source catalogue	FK4, catalogue number: 682
Durchmusterung	BD-21 4908
Boss General Catalogue	24856
Henry Draper Catalogue	166937

data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)

position and proper motion:

position (J2000)	RA: 18h 13.8min	DEC: -21° 4'
proper motion (J2000)	RA: 0.002 arcsec/a	DEC: 0.001 arcsec/a

double/multiple star system information:

component	year	number of measures	position angle	angular separation	magnitude of 1st component	magnitude of 2nd component	spectral class(es)	discoverer code
AB	1836	12	258°	16.9''	3.85	10.48	B8Iape	H 7
AC	1878	5	119°	25.8''	3.85	13.5	-	BU 292
AD	1835	11	312°	48.5''	3.85	9.69	B3	HJ 2822
AE	1835	10	115°	50''	3.85	9.25	-	HJ 2822
BD	1968	1	331°	40.6''	-	-	-	SLV
BE	1968	1	106°	64.5''	-	-	-	SLV

discoverer information:

discoverer code	discoverer	reference
H 7	Herschel, W.	-
BU 292	Burnham, S.W.	-
HJ 2822	Herschel, J.	-
SLV	Salukvadze, G.

notes:

note	H V 7. Mu Sgr. A is an Algol-type system and occultation binary.

data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)

position:

position (equinox 1950.0)

RA: 18h 10min 46.3sec

DEC: -21° 4' 25''

variability informations:

variability type	EA+ACYG	close binary eclipsing system pulsating variable star
magnitute at max. brightness	3.8
magnitute at min. brightness	3.88
photometric system	visual, photovisual or Johnson's V
epoch for maximum light [JD]	2444035 10. June 1979, 12:00:00 UT
period [d]	180.55
next maximum light [JD]	2451979.2 10. March 2001, 16:48:00 UT
duration of the eclipse	11 % of period

spectral information

spectral class

B8eqIa+B1.5V

references

to a study	Vol. III GCVS
to a chart/photograph	no chart is avaible, but the star is contained in the 'Bonner Durchmusterung'

miscanellous

ID in the GCVS catalogue	72/9012
constellation	Sagittarius
notes on existence	The star is equivalent to '07290171rho 1'.
There are notes in published catalog.

variability type description

variability type	description
EA	Eclipsing binary systems. These are binary systems with orbital planes so close to the observer's line of sight (the inclination i of the orbital plane to the plane orthogonal to the line of sight is close to 90 deg) that the components periodically eclipse each other. Consequently, the observer finds changes of the apparent combined brightness of the system with the period coincident with that of the components' orbital motion. EA Algol (Beta Persei)-type eclipsing systems. Binaries with spherical or slightly ellipsoidal components. It is possible to specify, for their light curves, the moments of the beginning and end of the eclipses. Between eclipses the light remains almost constant or varies insignificantly because of reflection effects, slight ellipsoidality of components, or physical variations. Secondary minima may be absent. An extremely wide range of periods is observed, from 0.2 to >= 10000 days. Light amplitudes are also quite different and may reach several magnitudes. EB Beta Lyrae-type eclipsing systems. These are eclipsing systems having ellipsoidal components and light curves for which it is impossible to specify the exact times of onset and end of eclipses because of a continuous change of a system's apparent combined brightness between eclipses; secondary minimum is observed in all cases, its depth usually being considerably smaller than that of the primary minimum; periods are mainly longer than 1 day. The components generally belong to early spectral types (B-A). Light amplitudes are usually <2 mag in V. EW W Ursae Majoris-type eclipsing variables. These are eclipsers with periods shorter than 1 days, consisting of ellipsoidal components almost in contact and having light curves for which it is impossible to specify the exact times of onset and end of eclipses. The depths of the primary and secondary minima are almost equal or differ insignificantly. Light amplitudes are usually <0.8 mag in V. The components generally belong to spectral types F-G and later.
ACYG	Variables of the Alpha Cygni type, which are nonradially pulsating supergiants of Bep-AepIa spectral types. The light changes with amplitudes of the order of 0.1 mag often seem irregular, being caused by the superposition of many oscillations with close periods. Cycles from several days to several weeks are observed.