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	Alfirk, b Cep, bet Cep, 8 Cep, HR 8238, HD 205021, SAO 10057, BD +69 1173, FK5: 809, WDS 21287+7034A
other names	Alphirk
constellation	Cepheus

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

note (category: star names):

Alfirk; Alphirk.

position, motion, parallax:

position (J2000)	RA: 21h 28min 39,6sec	DEC: +70° 33' 39''
position (2001,21)	RA: 21h 28min 41sec	DEC: +70° 33' 58''
position (B1900)	RA: 21h 27min 22,2sec	DEC: +70° 7' 18''
proper motion (J2000)	RA: 0,01 arcsec/a	DEC: 0,007 arcsec/a
radial velocity	-8 km/s note: spectroscopic binaries note: orbital data avaible
rotational velocity	28 km/s (uncertain) (variable)
trigonometric parallax	0,014 arcsec
galactic coordinates	longitude: 107,54°	latitude: 14,03°

note (category: dynamical parallaxes):

0.004".

magnitude

visual magnitude

3,23 (V on UBV Johnson system)

spectral / color information

spectral class	B1IV
B-V-magnitude	-0,22
U-B-magnitude	-0,95
R-I-magnitude

variability information

variable star identification

Bet Cep

note (category: variability):

ADS 15032A, Beta C 3.16 - 3.27V, 0.1904881d, modulation period 10.893d. SiIV and CIV vary. Satellite UV obs. indicate temp. varies 1340d, max./min. radius 1.038.

double/multiple star system information

number of components of multiple star system	3
separation	13,4 arcsec
mag difference (of double or brightest multiple)	4,6
component ID	AB

note (category: double and multiple data):

ADS 15032AB, 50y. B, 7.84V, +0.18(B-V), +0.06(U-B), A2.5V, vsini 60:k/s. Third component discovered by speckle interferometry, mag. diff about 4v. Sep. 0.025". Possible circumstellar material.

note (category: spectroscopic binaries):

ADS 15032A, 10.893d, K 3.1k/s, V0 -3.1k/s, asini 0.397. Resolved by speckle interferometry 1986.45, sep. 0.11".

miscellaneous information

note (category: group membership):

Cep OB1.

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

position, motion, parallax:

position (J2000)	RA: 21h 28min 39,6sec	DEC: +70° 33' 38,61''	±0,06 arcsec	source: 15
position (2001,21)	RA: 21h 28min 41sec	DEC: +70° 33' 58''	JD: 2451987,35
proper motion (J2000)	RA: 0,0021 arcsec/a	DEC: 0,007 arcsec/a		source: 25
radial velocity	-8 km/s			source: 25
trigonometric parallax	0,014 arcsec		±0,001 arcsec	source: 25
galactic coord. (B1950)	longitude: 107,54°	latitude: 14,03°

magnitude:

visual	3,2 (observed)	source: 31
photovisual	3,3	source: 2

spectral information:

spectral class	B1		source: 96
Morgan-Keenan	B1IV		source: 25
B-magnitude	3,01 ±0,05	B-V-magnitude	-0,22
U-magnitude	2,06 ±0,05	U-B-magnitude	-0,95

variability information:

source of data: 30

variability type	140
var. amplitude	0,11
var. period	0,19
var. epoch	2440445 11. August 1969, 12:00:00 UT
next max light	2451987,5 19. March 2001, 00:00:00 UT

double/multiple star system information:

source of data: 19

separation between brightest and second brightest component	0,1 arcsec
position angle	51 °

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
31	CRM' (non-GCVS variable data)
Warren, W.H. Jr., Northern Hemisphere Catalog of Red Magnitudes, 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: 21h 28min 1,326sec	DEC: +70° 20' 27,85''	±0,003 arcsec
position (2001,21)	RA: 21h 28min 40sec	DEC: +70° 33' 58''	JD: 2451987,35
position (J2000)	RA: 21h 28min 39,628sec	DEC: +70° 33' 38,67''
proper motion B1950 (FK4)	RA: 0,002 arcsec/a	DEC: 0,013 arcsec/a	±0,001 arcsec/a in RA ±0,001 arcsec/a in DEC
proper motion J2000 (FK5)	RA: 0,0024 arcsec/a	DEC: 0,008 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	3,3 (accuracy: 2 decimals)
source of visual magnitude data	Taken from the "Henry Draper Catalogue".

spectral information:

spectral class	B1
source of spectral data	Taken from the Henry Draper Catalogue or no spectrum in source catalog.

catalogues

source catalogue	FK4, catalogue number: 809
Durchmusterung	BD+69 1173
Boss General Catalogue	30118
Henry Draper Catalogue	205021

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

position and proper motion:

position (J2000)	RA: 21h 28,7min	DEC: +70° 34'
proper motion (J2000)	RA: 0,01 arcsec/a	DEC: 0,007 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
Aa	1971	30	48°	0,3''	3,2	-	B2III	LAB
	1990		51°	0,1''
Aa-B	1832	59	251°	13,4''	3,2	7,8	-	STF2806
	1975		249°	-

discoverer information:

discoverer code	discoverer	reference
LAB	Labeyrie et al
STF2806	Struve, F.G.W.	-

notes:

note	Beta Cep. The third component was discovered recently by speckle interferometry.

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

position:

position (equinox 1950.0)

RA: 21h 28min 1,3sec

DEC: +70° 20' 28''

variability informations:

variability type	BCEP	pulsating variable star
magnitute at max. brightness	3,16
magnitute at min. brightness	3,27
photometric system	visual, photovisual or Johnson's V
epoch for maximum light [JD]	2440444,625 11. August 1969, 03:00:00 UT
period [d]	0,1904881
next maximum light [JD]	2451987,4419076 18. March 2001, 22:36:21 UT
rising time	50 % of period

spectral information

spectral class

B2IIIeV

references

to a study	Vol. I GCVS (see Kholopov et al. 1985-1988)
to a chart/photograph	no chart is avaible, but the star is contained in the 'Bonner Durchmusterung'

miscanellous

ID in the GCVS catalogue	20/9002
constellation	Cepheus
notes on existence	The star is equivalent to '0209004 del'.
There are notes in published catalog.

variability type description

variability type

description

BCEP

Variables of the Beta Cephei type (Beta Cep, Beta CMa), which are pulsating O8-B6 I-V stars with periods of light and radial-velocity variations in the range of 0.1 - 0.6 days and light amplitudes from 0.01 to 0.3 mag in V. The light curves are similar in shape to average radial-velocity curves but lag in phase by a quarter of the period, so that maximum brightness corresponds to maximum contraction, i.e., to minimum stellar radius. The majority of these stars probably show radial pulsations, but some (V649 Per) display nonradial pulsations; multiperiodicity is characteristic of many of these stars.