V4200 Sagittarii

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

position, motion, parallax:

position (J2000)	RA: 19h 54min 17.7sec	DEC: -23° 56' 28''
position (2000.72)	RA: 19h 54min 21sec	DEC: -23° 56' 21''
position (B1900)	RA: 19h 48min 18.4sec	DEC: -24° 11' 23''
proper motion (J2000)	RA: -0.131 arcsec/a	DEC: -0.414 arcsec/a
radial velocity	-7 km/s note: spectroscopic binaries, double lined spectra
rotational velocity	=<8 km/s (uncertain) (variable)
trigonometric parallax	0.075 arcsec
galactic coordinates	longitude: 17.18°	latitude: -23.91°

magnitude

visual magnitude

6.18
(V on UBV Johnson system)

spectral / color information

spectral class	K2V
B-V-magnitude	1.02
U-B-magnitude	0.94
R-I-magnitude

variability information

variable star identification

Var?

note (category: variability):

BY Dra type predicted, but variability not yet detected.

double/multiple star system information

separation	31.5 arcsec
mag difference (of double or brightest multiple)	4

note (category: double and multiple data):

Optical.

note (category: spectroscopic binaries):

46.817d, e 0.692, K(A) 48.8 k/s, K(B) 48.7 k/s, V0 -5.1 k/s, m(A)sin3i = m(B)sin3i = 0.85, a(A)sini 22.7, a(B)sini 22.6.

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

position, motion, parallax:

position (J2000)	RA: 19h 54min 17.755sec	DEC: -23° 56' 27.82''	ą0.19 arcsec	source: 16
position (2000.72)	RA: 19h 54min 21sec	DEC: -23° 56' 21''	JD: 2451809.16
proper motion (J2000)	RA: -0.0088 arcsec/a	DEC: -0.409 arcsec/a		source: 25
radial velocity	-7 km/s			source: 25
trigonometric parallax	0.075 arcsec		ą0.007 arcsec	source: 25
galactic coord. (B1950)	longitude: 17.19°	latitude: -23.91°

magnitude:

visual	6.18 (observed)	source: 25
photovisual	6.1	source: 16

spectral information:

spectral class	K0		source: 96
Morgan-Keenan	K3VaCN1		source: 25
B-magnitude	7.2 ą0.05	B-V-magnitude	1.02
U-magnitude	8.14 ą0.05	U-B-magnitude	0.94

double/multiple star system information:

source of data: 19

separation between brightest and second brightest component	31.5 arcsec
magnitude difference between brightest and second brightest component	4.1
position angle	46 °

sources:

16	PPM North and PPM South Catalogs and PPM Supplement
Roser, S., and U. Bastian, "Catalogue of Positions and Proper Motions," A&AS, Vol. 74, p. 449, 1988, and Bastian, U., et al., "Catalogue of Positions and Proper Motions - South," 1993
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
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: 19h 51min 18.168sec	DEC: -24° 4' 1.24''	ą0.018 arcsec
position (2000.72)	RA: 19h 54min 21sec	DEC: -23° 56' 1''	JD: 2451809.16
position (J2000)	RA: 19h 54min 17.692sec	DEC: -23° 56' 28.26''
proper motion B1950 (FK4)	RA: -0.0097 arcsec/a	DEC: -0.412 arcsec/a	ą0.004 arcsec/a in RA ą0.004 arcsec/a in DEC
proper motion J2000 (FK5)	RA: -0.0096 arcsec/a	DEC: -0.414 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	6.3 (accuracy: 2 decimals)
source of visual magnitude data	Taken from Harvard or San Luis photometry.

spectral information:

spectral class	K0
source of spectral data	Taken from the Henry Draper Catalogue or no spectrum in source catalog.

remarks for duplicity and variability

Double star in Aitken's Double Star Catalogue (Aitken 1932)

catalogues

source catalogue	GC, catalogue number: 27542
Durchmusterung	CD-2415668
Boss General Catalogue	27542
Henry Draper Catalogue	188088

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

position and proper motion:

position (J2000)	RA: 19h 54.3min	DEC: -23° 56'
proper motion (J2000)	RA: -0.121 arcsec/a	DEC: -0.409 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
-	1877	18	142°	18.3''	6.18	10.3	K3IV	HJ 2904
-	1965	18	46°	31.5''	6.18	10.3	K3IV	HJ 2904

discoverer information:

discoverer code	discoverer	reference
HJ 2904	Herschel, J.	-

notes:

note	A is a spectroscopic binary.

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

position:

position (equinox 1950.0)

RA: 19h 51min 18.2sec

DEC: -24° 4' 1''

variability informations:

variability type	BY	rotating variable star
magnitute at max. brightness	6.18
magnitute amplitude	0.07
photometric system	visual, photovisual or Johnson's V

references

to a study	J.T.Hooten, D.S.Hall, ApJ Suppl 74, No.1, 225, 1990.
to a chart/photograph	no chart is avaible, but the star is contained in the 'Cordoba Durchmusterung'

miscanellous

ID in the GCVS catalogue	72/4200
constellation	Sagittarius
notes on existence	The star is equivalent to '71399'.

variability type description

variability type

description

BY Draconis-type variables, which are emission-line dwarfs of dKe-dMe spectral type showing quasiperiodic light changes with periods from a fraction of a day to 120 days and amplitudes from several hundredths to 0.5 mag in V. The light variability is caused by axial rotation of a star with a variable degree of nonuniformity of the surface brightness (spots) and chromospheric activity.
Some of these stars also show flares similar to those of UV Cet stars, and in those cases they also belong to the latter type and are simultaneously considered eruptive variables.