catalogues and names

Smithsonian Astrophysical Observatory Star Catalog

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

catalogues and names

catalogues and names

AU Peg, SAO 107100, BD +17 4572

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

position and proper motion:

position (B1950)	RA: 21h 21min 40.385sec	DEC: +18° 3' 49.37''	±0.019 arcsec
position (2000.72)	RA: 21h 24min 2sec	DEC: +18° 16' 56''	JD: 2451806.31
position (J2000)	RA: 21h 24min 0.3sec	DEC: +18° 16' 45.67''
proper motion B1950 (FK4)	RA: 0.0005 arcsec/a	DEC: 0.016 arcsec/a	±0.007 arcsec/a in RA ±0.009 arcsec/a in DEC
proper motion J2000 (FK5)	RA: 0.0005 arcsec/a	DEC: 0.013 arcsec/a
source of proper motion data	Determined by source catalog

magnitude:

visual	9.2 (accuracy: 1 decimal)
source of visual magnitude data	Taken from AGK1.

spectral information:

source of spectral data

Taken from the Henry Draper Catalogue or no spectrum in source catalog.

catalogues

source catalogue	Yale Transactions 18, catalogue number: 8730
Durchmusterung	BD+17 4572

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

position:

position (equinox 1950.0)

RA: 21h 21min 40.4sec

DEC: +18° 3' 49''

variability informations:

variability type	CEP	pulsating variable star
magnitute at max. brightness	8.98
magnitute at min. brightness	9.47
photometric system	visual, photovisual or Johnson's V
epoch for maximum light [JD]	2442303.61 13. September 1974, 02:38:24 UT
period [d]	2.4015
next maximum light [JD]	2451806.3455 18. September 2000, 20:17:31 UT
rising time	33 % of period (uncertain)

spectral information

spectral class

F8

references

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

miscanellous

ID in the GCVS catalogue	62/74
constellation	Pegasus
notes on existence	The star is equivalent to '0620075 AV'.
There are notes in published catalog.

variability type description

variability type

description

CEP

Cepheids. Radially pulsating, high luminosity (classes Ib-II) variables with periods in the range of 1-135 days and amplitudes from several hundredths to 2 mag in V (in the B band, the amplitudes are greater). Spectral type at maximum light is F; at minimum, the types are G-K. The longer the period of light variation,the later is the spectral type. The maximum of the surface-layer expansion velocity almost coinciding with maximum light.