W Orionis

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

position, motion, parallax:

position (J2000)	RA: 5h 5min 23.7sec	DEC: +1° 10' 39''
position (B1900)	RA: 5h 0min 13.8sec	DEC: +1° 2' 25''
proper motion (J2000)	RA: 0.012 arcsec/a	DEC: -0.007 arcsec/a
radial velocity	17 km/s note: suspected variable radial velocity
galactic coordinates	longitude: 199.01°	latitude: -22.82°

magnitude

visual magnitude

6.17
(V on UBV Johnson system)

spectral / color information

spectral class	C6II
B-V-magnitude	3.45
U-B-magnitude	6.5
R-I-magnitude
IR-note	object is infrared source (NASA merged infrared catalogue, Schmitz et al., 1978)

variability information

variable star identification

W Ori

note (category: variability):

SRb 8.2 - 12.4p, 212d. Mean mag. varies in period 2450d.

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

position, motion, parallax:

position (J2000)	RA: 5h 5min 23.793sec	DEC: +1° 10' 39.4''	ą0.43 arcsec	source: 16
proper motion (J2000)	RA: 0.0016 arcsec/a	DEC: 0 arcsec/a		source: 25
radial velocity	17 km/s			source: 25
galactic coord. (B1950)	longitude: 199.01°	latitude: -22.82°

magnitude:

visual	6.17 (observed)	source: 25
photographic	10	source: 16

spectral information:

spectral class	Nb		source: 29
Morgan-Keenan	C5,4		source: 25
B-magnitude	9.62 ą0.05	B-V-magnitude	3.45
U-magnitude	16.12 ą0.05	U-B-magnitude	6.5

variability information:

source of data: 30

variability type	194
var. amplitude	4.2
var. period	212

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
25	Bright Star Catalogue, 5th edition
Hoffleit, D. and Warren, W.H. Jr., The Bright Star Catalogue, 5th Revised Edition, Version 2, 1994
29	SAOJ2000
SAO on FK5 at J2000, 1989
30	GCVS, 4th edition
Kholopov, P.N., et al., General Catalogue of Variable Stars, fourth edition, Moscow: Nauka Publishing House, 1985-88

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

position and proper motion:

position (B1950)	RA: 5h 2min 48.658sec	DEC: +1° 6' 37.21''	ą0.037 arcsec
position (J2000)	RA: 5h 5min 23.734sec	DEC: +1° 10' 38.88''
proper motion B1950 (FK4)	RA: 0.0005 arcsec/a	DEC: -0.006 arcsec/a	ą0.007 arcsec/a in RA ą0.005 arcsec/a in DEC
proper motion J2000 (FK5)	RA: 0.0008 arcsec/a	DEC: -0.007 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	5.9 (accuracy: 1 decimal)
source of visual magnitude data	Source cited in source catalog introduction.

spectral information:

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

remarks for duplicity and variability

Variable star in visual magnitude in source catalog

catalogues

source catalogue	GC, catalogue number: 6221
Durchmusterung	BD+00 939
Boss General Catalogue	6221
Henry Draper Catalogue	32736

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

position:

position (equinox 1950.0)

RA: 5h 2min 48.7sec

DEC: +1° 6' 37''

variability informations:

variability type	SRB	pulsating variable star
magnitute at max. brightness	8.2
magnitute at min. brightness	12.4
photometric system	photographic magnitudes
period [d]	212

spectral information

spectral class

C5,4(N5)

references

to a study	Vol. I GCVS (see Kholopov et al. 1985-1988)
to a chart/photograph	Vol. I GCVS (see Kholopov et al. 1985-1988)

miscanellous

ID in the GCVS catalogue	60/6
constellation	Orion
notes on existence	The star is equivalent to '0600007 X'.
There are notes in published catalog.

variability type description

variability type

description

SRB

Semiregular variables, which are giants or supergiants of intermediate and late spectral types showing noticeable periodicity in their light changes, accompanied or sometimes interrupted by various irregularities. Periods lie in the range from 20 to >2000 days, while the shapes of the light curves are rather different and variable, and the amplitudes may be from several hundredths to several magnitudes (usually 1-2 mag in V).

SRA
Semiregular late-type (M, C, S or Me, Ce, Se) giants displaying persistent periodicity and usually small (<2.5 mag in V) light amplitudes (Z Aqr). Amplitudes and light-curve shapes generally vary and periods are in the range of 35-1200 days. Many of these stars differ from Miras only by showing smaller light amplitudes;

SRB
Semiregular late-type (M, C, S or Me, Ce, Se) giants with poorly defined periodicity (mean cycles in the range of 20 to 2300 days) or with alternating intervals of periodic and slow irregular changes, and even with light constancy intervals (RR CrB, AF Cyg). Every star of this type may usually be assigned a certain mean period (cycle), which is the value given in the Catalogue. In a number of cases, the simultaneous presence of two or more periods of light variation is observed;

SRC
Semiregular late-type (M, C, S or Me, Ce, Se) supergiants (Mu Cep) with amplitudes of about 1 mag and periods of light variation from 30 days to several thousand days;

SRD
Semiregular variable giants and supergiants of F, G, or K spectral types, sometimes with emission lines in their spectra. Amplitudes of light variation are in the range from 0.1 to 4 mag, and the range of periods is from 30 to 1100 days (SX Her, SV UMa).