RY Sagittarii
catalogues and names
| catalogues and names | RY Sgr, HR 7296, HD 180093, SAO 211117, CD -33 14076 |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
position, motion, parallax:
| position (J2000) | RA: 19h 16min 32.8sec | DEC: -33° 31' 18'' | ||
| position (2000.74) | RA: 19h 16min 36sec | DEC: -33° 31' 13'' | ||
| position (B1900) | RA: 19h 10min 0.9sec | DEC: -33° 41' 50'' | ||
| proper motion (J2000) | RA: 0.012 arcsec/a | DEC: 0.024 arcsec/a | ||
| radial velocity | -23 km/s note: variable radial velocity |
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| galactic coordinates | longitude: 4.43° | latitude: -19.45° | ||
| note (category: radial and/or rotational velocities): | 38.6d. |
magnitude
| visual magnitude | 6.25 (V on UBV Johnson system) |
spectral / color information
| spectral class | G0Ipe(C1,0) |
| B-V-magnitude | 0.02 |
| U-B-magnitude | -0.07 |
| IR-note | object is infrared source (NASA merged infrared catalogue, Schmitz et al., 1978) |
| note (category: spectra): | Hydrogen deficient carbon star. |
| note (category: colors): | Possible extinction by circumstellar dust. |
variability information
| variable star identification | RY Sgr |
| note (category: variability): | RCB 6.0 - >15.0v. Also pulsations 38.454d, changing amplitude. Observations 1984-86 indicate semiregular pulsations of 33 to 40d, 6.13 - 6.78V, 0.38 - 0.76(B-V), -0.09 to +0.52(U-B). |
miscellaneous information
| note (category: miscellaneous): | Possibly high luminosity evolved helium star. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 19h 16min 32.8sec | DEC: -33° 31' 20.5'' | ±0.19 arcsec | source: 16 |
| position (2000.74) | RA: 19h 16min 36sec | DEC: -33° 31' 15'' | JD: 2451813.20 | |
| proper motion (J2000) | RA: 0.0013 arcsec/a | DEC: -0.003 arcsec/a | source: 25 | |
| radial velocity | -23 km/s | source: 25 | ||
| galactic coord. (B1950) | longitude: 4.44° | latitude: -19.45° | ||
magnitude:
| visual | 6.25 (observed) | source: 25 |
| photovisual | 8.6 | source: 16 |
spectral information:
| spectral class | G0 | source: 96 | |
| Morgan-Keenan | M5e | source: 25 | |
| B-magnitude | 6.27 ±0.05 | B-V-magnitude | 0.02 |
| U-magnitude | 6.2 ±0.05 | U-B-magnitude | -0.07 |
variability information:
| variability type | 230 |
| var. amplitude | 8.2 |
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 (B1950) | RA: 19h 13min 16.933sec | DEC: -33° 36' 40.91'' | ±0.067 arcsec |
| position (2000.74) | RA: 19h 16min 36sec | DEC: -33° 31' 14'' | JD: 2451813.20 |
| position (J2000) | RA: 19h 16min 32.758sec | DEC: -33° 31' 17.85'' | |
| proper motion B1950 (FK4) | RA: 0.001 arcsec/a | DEC: 0.025 arcsec/a | ±0.012 arcsec/a in RA ±0.012 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: 0.0009 arcsec/a | DEC: 0.024 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 6.1 (accuracy: 1 decimal) |
| source of visual magnitude data | Source cited in source catalog introduction. |
spectral information:
| spectral class | G0p |
| 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: 26544 |
| Durchmusterung | CD-3314076 |
| Boss General Catalogue | 26544 |
| Henry Draper Catalogue | 180093 |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
| position (equinox 1950.0) | RA: 19h 13min 16.9sec | DEC: -33° 36' 41'' |
variability informations:
| variability type | RCB | eruptive variable star |
| magnitute at max. brightness | 5.8 | |
| magnitute at min. brightness | 14 | |
| photometric system | visual, photovisual or Johnson's V |
spectral information
| spectral class | G0Iaep(C1,0) |
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 | 72/17 |
| constellation | Sagittarius |
| notes on existence | The star is equivalent to '0720018 RZ'. |
| There are notes in published catalog. | |
variability type description
| variability type | description |
| RCB | Variables of the R Coronae Borealis type. These are hydrogen-poor,carbon- and helium-rich, high-luminosity stars belonging to the spectral types Bpe-R, which are simultaneously eruptive and pulsating variables. They show slow nonperiodic fadings by 1-9 mag in V lasting from a month or more to several hundred days. These changes are superposed on cyclic pulsations with amplitudes up to several tenths of a magnitude and periods in the range 30-100 days. |