R Sct

The object was found in the following catalogues:
  1. The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version)

  2. SKY2000 - Master Star Catalog

  3. Smithsonian Astrophysical Observatory Star Catalog

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

catalogues and names R Sct, HR 7066, HD 173819, SAO 142620

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

object is infrared source (NASA merged infrared catalogue, Schmitz et al., 1978)

position, motion, parallax:

position (J2000) RA: 18h 47min 29sec DEC: -5 42' 18''
position (J1900) RA: 18h 42min 8,6sec DEC: -5 48' 45''
proper motion (J2000) RA: -0,041 arcsec/a DEC: -0,028 arcsec/a
radial velocity 44 km/s
note: variable radial velocity
trigonometric parallax 0,001 arcsec


visual magnitude 5,2
(V on UBV Johnson system)

spectral / color information

spectral class K0Ibp
B-V-magnitude 1,47
U-B-magnitude 1,64
R-I-magnitude 0,77
note (category: spectra): H alpha emission. Also classified G0eIa-K0pIb.

variability information

variable star identification R Sct
note (category: variability): Discovered by Pigott in 1795. RVa 4.45 - 8.20V, 140.05d, period varies. Variable He 10830 and Ti emission. Largest intrinsic polarization in UV at minimum light. Light and RV periods differ.

miscellaneous information

note (category: group membership): Sct OB2.

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

position, motion, parallax:

position (J2000) RA: 18h 47min 28,962sec DEC: -5 42' 18,58'' 0,19 arcsec source: 16
proper motion (J2000) RA: -0,0029 arcsec/a DEC: -0,027 arcsec/a source: 25
radial velocity 44 km/s source: 25
trigonometric parallax 0,001 - source: 25
galactic coord. (B1950) longitude: 27,41 latitude: -1,72
GCI unit vector (J2000) X: 0,204684 Y: -0,973767 Z: -0,099409


visual 5,2 (observed) source: 25
photovisual 4,6 source: 16

spectral information:

spectral class K0 source: 96
Morgan-Keenan K0Ibp source: 25
B-magnitude 6,67 0,05 B-V-magnitude 1,47
U-magnitude 8,31 0,05 U-B-magnitude 1,64

variability information:

source of data: 30
variability type 131
var. amplitude 4,4
var. period 146,5
var. epoch 2444872
24. September 1981, 12:00:00 UT
next max light 2451757,5
1. August 2000, 00:00:00 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
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 (J1950) RA: 18h 44min 48,745sec DEC: -5 45' 37,4'' 0,026 arcsec
position (J2000) RA: 18h 47min 28,964sec DEC: -5 42' 18,32''
proper motion J1950 (FK4) RA: -0,003 arcsec/a DEC: -0,028 arcsec/a 0,004 arcsec/a in RA
0,004 arcsec/a in DEC
proper motion J2000 (FK5) RA: -0,0028 arcsec/a DEC: -0,028 arcsec/a
source of proper motion data Determined by source catalog


visual 4,5 (accuracy: 1 decimal)
source of visual magnitude data Source cited in source catalog introduction.

spectral information:

spectral class K0p
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: 25735
Durchmusterung BD-05 4760
Boss General Catalogue 25735
Henry Draper Catalogue 173819

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


position (J1950) RA: 18h 44min 48,7sec DEC: -5 45' 37''

variability informations:

variability type RVA pulsating variable star
magnitute at max. brightness 4,2
magnitute at min. brightness 8,6
photometric system visual, photovisual or Johnson's V
epoch for maximum light [JD] 2444872
24. September 1981, 12:00:00 UT
period [d] 146,5
next maximum light [JD] 2451757,5
1. August 2000, 00:00:00 UT

spectral information

spectral class G0Iae-K2p(M3)Ibe


to a study the main characteristics of the star was determined by the authors themselves
to a chart/photograph Vol. I GCVS (see Kholopov et al. 1985-1988)


ID in the GCVS catalogue 75/1
constellation Sextans
notes on existence The star is equivalent to '0750002 S'.
There are notes in published catalog.

variability type description

variability type description
RVA Variables of the RV Tauri type. These are radially pulsating supergiants having spectral types F-G at maximum light and K-M at minimum. The light curves are characterized by the presence of double waves with alternating primary and secondary minima that can vary in depth so that primary minima may become secondary and vice versa. The complete light amplitude may reach 3-4 mag in V.
Periods between two adjacent primary minima (usually called formal periods) lie in the range 30-150 days (these are the periods appearing in the Catalogue). Two subtypes, RVA and RVB, are recognized:

RV Tauri variables that do not vary in mean magnitude (AC Her);

RV Tauri variables that periodically (with periods from 600 to 1500 days and amplitudes up to 2 mag in V) vary in mean magnitude (DF Cyg, RV Tau).