catalogues and names

SKY2000 - Master Star Catalog

Smithsonian Astrophysical Observatory Star Catalog

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

catalogues and names

catalogues and names

V1719 Cyg, HD 200925, SAO 33108, BD +50 3259

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

position, motion, parallax:

position (J2000)	RA: 21h 4min 32.914sec	DEC: +50° 47' 3.27''	±0.42 arcsec	source: 16
position (2000.73)	RA: 21h 4min 34sec	DEC: +50° 47' 14''	JD: 2451810.88
proper motion (J2000)	RA: -0.0005 arcsec/a	DEC: -0.007 arcsec/a		source: 16
radial velocity	15 km/s			source: 11
galactic coord. (B1950)	longitude: 90.99°	latitude: 2.55°

magnitude:

visual	7.95 (observed)	source: 30
photovisual	8.2	source: 2
photographic	8.2	source: 16

spectral information:

spectral class	F5		source: 96
Morgan-Keenan	F5III		source: 98
B-magnitude	8.48 ±0.02	B-V-magnitude	0.42

variability information:

source of data: 30

variability type	122
var. amplitude	0.38
var. period	0.27
var. epoch	2443777 25. September 1978, 12:00:00 UT
next max light	2451811.12 23. September 2000, 14:52:48 UT

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
11	General Catalogue of Stellar Radial Velocities
Wilson, R.E., General Catalogue of Stellar of Stellar Radial Radial Velocities, Washington, DC: Carnegie Institute of Washington, 1953
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
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
98	SKYMAP Master Catalog Version 3.7
Reference from Value 97 [original data sources Catalog Version 3.7 are identified in SKYMAP Version 3.7]

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

position and proper motion:

position (B1950)	RA: 21h 2min 55.883sec	DEC: +50° 35' 3.51''	±0.014 arcsec
position (2000.73)	RA: 21h 4min 34sec	DEC: +50° 47' 15''	JD: 2451810.88
position (J2000)	RA: 21h 4min 32.921sec	DEC: +50° 47' 3.6''
proper motion B1950 (FK4)	RA: -0.0005 arcsec/a	DEC: 0.004 arcsec/a	±0.007 arcsec/a in RA ±0.007 arcsec/a in DEC
proper motion J2000 (FK5)	RA: -0.0001 arcsec/a	DEC: 0.001 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	8 (accuracy: 1 decimal)
source of visual magnitude data	Taken from AGK1.
photographic	8.3 (accuracy: 2 decimals)
source of photographic magnitude data	Columbia Contributions Numbers 30 and 31 (Schilt and Hill 1937, 1938)

spectral information:

spectral class	F5
source of spectral data	Taken from the HD with M stars reclassified by Miss Cannon.

catalogues

source catalogue	Yale Transactions 26 Part II, catalogue number: 6886
Durchmusterung	BD+50 3259
Henry Draper Catalogue	200925

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

position:

position (equinox 1950.0)

RA: 21h 2min 55.9sec

DEC: +50° 35' 4''

variability informations:

variability type	RRC	pulsating variable star
magnitute at max. brightness	7.95
magnitute at min. brightness	8.33
photometric system	visual, photovisual or Johnson's V
epoch for maximum light [JD]	2443776.715 25. September 1978, 05:09:36 UT
period [d]	0.267299
next maximum light [JD]	2451810.921043 23. September 2000, 10:06:18 UT
rising time	49 % of period

spectral information

spectral class

F5III

references

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

miscanellous

ID in the GCVS catalogue	31/1719
constellation	Cygnus
notes on existence	The star is equivalent to '0311720 V1720'.
There are notes in published catalog.

variability type description

variability type

description

RRC

Variables of the RR Lyrae type, which are radially-pulsating giant A-F stars having amplitudes from 0.2 to 2 mag in V. Cases of variable light-curve shapes as well as variable periods are known. If these changes are periodic, they are called the "Blazhko effect." Traditionally, RR Lyrae stars are sometimes called short-period Cepheids or cluster-type variables. The majority of these stars belong to the spherical component of the Galaxy; they are present, sometimes in large numbers, in some globular clusters, where they are known as pulsating horizontal-branch stars. Like Cepheids, maximum expansion velocities of surface layers for these stars practically coincide with maximum light. RR(B) RR Lyrae variables showing two simultaneously operating pulsation modes, the fundamental tone with the period P0 and the first overtone, P1 (AQ Leo). The ratio P1/P0 is approximately 0.745; RRAB RR Lyrae variables with asymmetric light curves (steep ascending branches), periods from 0.3 to 1.2 days, and amplitudes from 0.5 to 2 mag in V; RRC RR Lyrae variables with nearly symmetric, sometimes sinusoidal, light curves, periods from 0.2 to 0.5 days, and amplitudes not greater than 0.8 mag in V (SX UMa).