RR Lyr

The object was found in the following catalogues:
  1. SKY2000 - Master Star Catalog

  2. Smithsonian Astrophysical Observatory Star Catalog

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

catalogues and names RR Lyr, HD 182989, SAO 48421

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

position, motion, parallax:

position (J2000) RA: 19h 25min 27,961sec DEC: +42 47' 3,66'' 0,35 arcsec source: 17
proper motion (J2000) RA: -0,0091 arcsec/a DEC: -0,196 arcsec/a source: 17
radial velocity -72 km/s source: 26
trigonometric parallax 0,011 0,001 arcsec source: 26
galactic coord. (B1950) longitude: 74,96 latitude: 12,3
GCI unit vector (J2000) X: 0,267389 Y: -0,683473 Z: 0,679241


visual 7,1 (observed) source: 31
photographic 8 source: 16

spectral information:

spectral class F5 source: 96
Morgan-Keenan A8-F7 source: 26
B-magnitude 7,36 0,2 B-V-magnitude 0,3
U-magnitude 7,57 0,032 U-B-magnitude 0,15

variability information:

source of data: 30
variability type 121
var. amplitude 1,06
var. period 0,57
var. epoch 2442923
24. May 1976, 12:00:00 UT
next max light 2451621,77
18. March 2000, 06:28:48 UT


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
Corbin, T.E., and S.E. Urban, Astrographic Catalog Reference Stars, United States Naval Observatory, 1991
26 Bright Star Supplement
Hoffleit, D. and Warren, W.H. Jr., A Supplement to the Bright Star Catalogue, 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 (J1950) RA: 19h 23min 52,14sec DEC: +42 41' 11,91'' 0,044 arcsec
position (J2000) RA: 19h 25min 27,833sec DEC: +42 47' 4,5''
proper motion J1950 (FK4) RA: -0,011 arcsec/a DEC: -0,184 arcsec/a 0,012 arcsec/a in RA
0,01 arcsec/a in DEC
proper motion J2000 (FK5) RA: -0,0105 arcsec/a DEC: -0,186 arcsec/a
source of proper motion data Determined by source catalog


visual 7,2 (accuracy: 1 decimal)
source of visual magnitude data Source cited in source catalog introduction.

spectral information:

spectral class F5
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


source catalogue GC, catalogue number: 26836
Durchmusterung BD+42 3338
Boss General Catalogue 26836
Henry Draper Catalogue 182989

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


position (J1950) RA: 19h 23min 52,1sec DEC: +42 41' 12''

variability informations:

variability type RRAB pulsating variable star
magnitute at max. brightness 7,06
magnitute at min. brightness 8,12
photometric system visual, photovisual or Johnson's V
epoch for maximum light [JD] 2442923,4193
24. May 1976, 22:03:48 UT
period [d] 0,56686776
next maximum light [JD] 2451621,43820944
17. March 2000, 22:31:01 UT
rising time 19 % of period

spectral information

spectral class A5.0-F7.0


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


ID in the GCVS catalogue 52/10
constellation Lyra
notes on existence The star is equivalent to '0520011 RS'.
There are notes in published catalog.

variability type description

variability type description
RRAB 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 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;

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;

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).