R Sct
| catalogues and names | R Sct, HR 7066, HD 173819, SAO 142620 |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
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 | |
magnitude
| 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 | |
magnitude:
| 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:
| 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 |
sources:
| 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 | ||
magnitude:
| 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 |
catalogues
| 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:
| 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 |
references
| 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) |
miscanellous
| 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: RVA RV Tauri variables that do not vary in mean magnitude (AC Her); RVB 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). |