beta Monocerotis

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

position, motion, parallax:

position (J2000)	RA: 6h 28min 49sec	DEC: -7° 1' 58''
position (2001,17)	RA: 6h 28min 52sec	DEC: -7° 2' 1''
position (B1900)	RA: 6h 23min 58sec	DEC: -6° 58' 8''
proper motion (J2000)	RA: -0,017 arcsec/a	DEC: 0 arcsec/a
radial velocity	20 km/s note: spectroscopic binaries note: orbital data avaible
rotational velocity	346 km/s (uncertain) (variable)
trigonometric parallax	0,021 arcsec
galactic coordinates	longitude: 216,66°	latitude: -8,21°

magnitude

visual magnitude

4,6
(V on UBV Johnson system)

spectral / color information

spectral class	B3Ve
B-V-magnitude	-0,1
U-B-magnitude	-0,63
R-I-magnitude

note (category: spectra):

Shell star with variable H alpha emission.

variability information

variable star identification

2977

note (category: variability):

Hydrogen lines var. K 30k/s. Shell line velocities do not correspond to orbital elements; may be due to gaseous ring.

double/multiple star system information

number of components of multiple star system	4
separation	7,1 arcsec
mag difference (of double or brightest multiple)	0,5
component ID	AB

note (category: double and multiple data):

Triple system with HR 2357 and 2358. Combined mag., color 3.74V, -0.15(B-V), all Be stars. AB, 17000y; AC, sep. 10", 29000y. Component D, 12.2v at 26" from A. Uncertain which of components A,B,C, HR 2356,7,8 is the light variable NSV 2977, for which the mag. 3.75V is a blend of all three.

note (category: spectroscopic binaries):

12.5y, K 30k/s, asini 1900. Shell oscillations. Spectrum var. 12.5y for 3.5 cycles, then ceased.

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

position, motion, parallax:

position (J2000)	RA: 6h 28min 48,96sec	DEC: -7° 1' 58,2''	ą0,76 arcsec	source: 18
position (2001,17)	RA: 6h 28min 52sec	DEC: -7° 2' 1''	JD: 2451972,92
proper motion (J2000)	RA: -0,0015 arcsec/a	DEC: 0,002 arcsec/a		source: 25
radial velocity	20 km/s			source: 25
trigonometric parallax	0,021 arcsec		ą0,002 arcsec	source: 25
galactic coord. (B1950)	longitude: 216,67°	latitude: -8,21°

magnitude:

visual	4,6 (observed)	source: 25
photovisual	4,7	source: 2
photographic	4,5	source: 2

spectral information:

spectral class	B2		source: 96
Morgan-Keenan	B3Ve		source: 25
B-magnitude	4,5 ą0,05	B-V-magnitude	-0,1
U-magnitude	3,87 ą0,05	U-B-magnitude	-0,63

double/multiple star system information:

source of data: 19

separation between brightest and second brightest component	7,2 arcsec
magnitude difference between brightest and second brightest component	0,8
position angle	132 °

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
18	Hipparcos Input Catalog Version 2 Annex
Turon, C., et al., "The Hipparcos Input Catalog, Version 2," Centre de Donnees Stellaires Information Bulletin, Vol. 43, p. 5, 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: 6h 26min 23,454sec	DEC: -6° 59' 58,06''	ą0,02 arcsec
position (2001,17)	RA: 6h 28min 52sec	DEC: -7° 2' 1''	JD: 2451972,92
position (J2000)	RA: 6h 28min 48,978sec	DEC: -7° 1' 58,44''
proper motion B1950 (FK4)	RA: -0,0015 arcsec/a	DEC: -0,002 arcsec/a	ą0,004 arcsec/a in RA ą0,003 arcsec/a in DEC
proper motion J2000 (FK5)	RA: -0,0011 arcsec/a	DEC: 0 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	4,7 (accuracy: 2 decimals)
source of visual magnitude data	Taken from Harvard or San Luis photometry.

spectral information:

spectral class	B2e
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: 8412
Durchmusterung	BD-06 1574
Boss General Catalogue	8412
Henry Draper Catalogue	45725

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

position and proper motion:

position (J2000)	RA: 6h 28,8min	DEC: -7° 2'
proper motion (J2000)	RA: -0,037 arcsec/a	DEC: 0 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	1831	87	132°	7,2''	4,7	5,2	B3Ve B3ne	STF 919
AC	1831	25	125°	9,9''	5,1	6,1	B3Ve B3e	STF 919
AD	1878	5	56°	25,9''	4,7	12,2	B3Ve	BU 570
BC	1831	78	102°	2,5''	5,7	6,2	B3Ve B3e	STF 919
BC	1992	78	107°	2,9''	5,7	6,2	B3Ve B3e	STF 919
Cc	1988	1	141°	0,3''	5,6	-	-	CHR 167

discoverer information:

discoverer code	discoverer	reference
STF 919	Struve, F.G.W.	-
BU 570	Burnham, S.W.	-
CHR 167	-	-

notes:

note	Beta Mon. A,B, and C are shell stars.

data from Combined General Catalogue of Variable Stars (suspected variables) (Kholopov+ 1998)

position:

position (equinox 1950.0)

RA: 6h 26min 23,7sec

DEC: -7° 0' 0''

variability informations:

magnitute at max. brightness	3,75
magnitute at min. brightness
photometric system	visual, photovisual or Johnson's V

spectral information

spectral class

references

to a study

671390D (designation: HR 2356/8)

miscanellous

There are notes in the published catalog (Kukarkin et al.(1982)).

catalogues and names	b Mon, NSV 02977, 11 Mon, HR 2356, HD 45725, SAO 133316, BD -6 1574, WDS 06288-0702A
constellation	Monoceros