catalogues and names

The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version)

SKY2000 - Master Star Catalog

Smithsonian Astrophysical Observatory Star Catalog

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

catalogues and names

catalogues and names	NT Vul, 15 Vul, HR 7653, HD 189849, SAO 88071, BD +27 3587, FK5: 1523
constellation	Vulpecula

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

position, motion, parallax:

position (J2000)	RA: 20h 1min 6.1sec	DEC: +27° 45' 13''
position (2000.72)	RA: 20h 1min 8sec	DEC: +27° 45' 20''
position (B1900)	RA: 19h 56min 58.9sec	DEC: +27° 28' 37''
proper motion (J2000)	RA: 0.059 arcsec/a	DEC: 0.005 arcsec/a
radial velocity	-21 km/s note: spectroscopic binaries note: orbital data avaible
rotational velocity	23 km/s (uncertain) (variable)
trigonometric parallax	0.03 arcsec
galactic coordinates	longitude: 65.3°	latitude: -1.34°

magnitude

visual magnitude

4.64 (V on UBV Johnson system)

spectral / color information

spectral class	A4III
B-V-magnitude	0.18
U-B-magnitude	0.16
R-I-magnitude

variability information

variable star identification

NT Vul

note (category: variability):

Amp. 0.03V, 14.0d.

double/multiple star system information

note (category: spectroscopic binaries):

3195d, K 4.6k/s, V0 -24.0k/s, e 0.76. Unresolved by speckle interferometry.

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

position, motion, parallax:

position (J2000)	RA: 20h 1min 6.05sec	DEC: +27° 45' 12.92''	±0.06 arcsec	source: 15
position (2000.72)	RA: 20h 1min 8sec	DEC: +27° 45' 20''	JD: 2451809.25
proper motion (J2000)	RA: 0.0044 arcsec/a	DEC: 0.005 arcsec/a		source: 25
radial velocity	-24 km/s			source: 25
trigonometric parallax	0.03 arcsec		±0.003 arcsec	source: 25
galactic coord. (B1950)	longitude: 65.31°	latitude: -1.34°

magnitude:

visual	4.64 (observed)	source: 25
photovisual	4.7	source: 2

spectral information:

spectral class	A5		source: 96
Morgan-Keenan	A4III		source: 25
B-magnitude	4.82 ±0.05	B-V-magnitude	0.18
U-magnitude	4.98 ±0.05	U-B-magnitude	0.16

variability information:

source of data: 30

variability type	160
var. amplitude	0.05
var. period	14
var. epoch	2441885 21. July 1973, 12:00:00 UT
next max light	2451811 23. September 2000, 12:00:00 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
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
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
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 59min 2.403sec	DEC: +27° 36' 51.44''	±0.004 arcsec
position (2000.72)	RA: 20h 1min 7sec	DEC: +27° 45' 20''	JD: 2451809.25
position (J2000)	RA: 20h 1min 6.06sec	DEC: +27° 45' 13.15''
proper motion B1950 (FK4)	RA: 0.0044 arcsec/a	DEC: 0.01 arcsec/a	±0.001 arcsec/a in RA ±0.001 arcsec/a in DEC
proper motion J2000 (FK5)	RA: 0.0045 arcsec/a	DEC: 0.008 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 the "Henry Draper Catalogue".

spectral information:

spectral class	A5
source of spectral data	Taken from the Henry Draper Catalogue or no spectrum in source catalog.

catalogues

source catalogue	FK4, catalogue number: 1523
Durchmusterung	BD+27 3587
Boss General Catalogue	27753
Henry Draper Catalogue	189849

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

position:

position (equinox 1950.0)

RA: 19h 59min 2.4sec

DEC: +27° 36' 51''

variability informations:

variability type	ACV	rotating variable star
magnitute at max. brightness	4.62
magnitute at min. brightness	4.67
photometric system	visual, photovisual or Johnson's V
epoch for maximum light [JD]	2441885.2 21. July 1973, 16:48:00 UT
period [d]	14
next maximum light [JD]	2451811.2 23. September 2000, 16:48:00 UT

spectral information

spectral class

A4IIIm

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	88/295
constellation	Vulpecula
notes on existence	The star is equivalent to '0880296 NU'.

variability type description

variability type

description

ACV

Alpha2 Canum Venaticorum variables. These are main-sequence stars with spectral types B8p-A7p and displaying strong magnetic fields. Spectra show abnormally strong lines of Si, Sr, Cr, and rare earths whose intensities vary with rotation. They exhibit magnetic field and brightness changes (periods of 0.5-160 days or more). The amplitudes of the brightness changes are usually withine 0.01-0.1 mag in V. ACVO Rapidly oscillating Alpha2 CVn variables. These are nonradially pulsating, rotating magnetic variables of Ap spectral type (DO Eri). Pulsation periods are in the range of 6-12 mmag (0.004-0.01 days), while amplitudes of light variation caused by the pulsation are about 0.01 mag in V. The pulsational variations are superposed on those caused by rotation.