HR 6980
catalogues and names
| catalogues and names | HR 6980, HD 171745, SAO 86224, BD +23 3385, WDS 18355+2336 |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
position, motion, parallax:
| position (J2000) | RA: 18h 35min 30.4sec | DEC: +23° 36' 20'' | ||
| position (B1900) | RA: 18h 31min 20.6sec | DEC: +23° 31' 28'' | ||
| proper motion (J2000) | RA: 0.004 arcsec/a | DEC: 0.005 arcsec/a | ||
| radial velocity | 16 km/s note: variable radial velocity |
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| dynamical parallax | 0.006 arcsec | |||
| galactic coordinates | longitude: 52.64° | latitude: 13.84° | ||
magnitude
| visual magnitude | 5.61 (V on UBV Johnson system) |
spectral / color information
| spectral class | G9III+G7III |
| B-V-magnitude | 1 |
| U-B-magnitude | 0.83 |
double/multiple star system information
| separation | 0.6 arcsec |
| mag difference (of double or brightest multiple) | 0.2 |
| note (category: double and multiple data): | 6.3 G9III, 6.5 G7III, 210.9y, a = 0.416" or 190.8y, a = 0.418". Combined mag., colors. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 18h 35min 30.406sec | DEC: +23° 36' 20.38'' | ±0.35 arcsec | source: 17 |
| proper motion (J2000) | RA: 0.0004 arcsec/a | DEC: 0.006 arcsec/a | source: 25 | |
| radial velocity | 16 km/s | source: 25 | ||
| galactic coord. (B1950) | longitude: 52.64° | latitude: 13.84° | ||
magnitude:
| visual | 5.61 (observed) | source: 25 |
| photovisual | 5.8 | source: 2 |
| photographic | 6.8 | source: 16 |
spectral information:
| spectral class | K0 | source: 96 | |
| Morgan-Keenan | G9III+G7III | source: 25 | |
| B-magnitude | 6.61 ±0.05 | B-V-magnitude | 1 |
| U-magnitude | 7.44 ±0.05 | U-B-magnitude | 0.83 |
double/multiple star system information:
| separation between brightest and second brightest component | 0.7 arcsec |
| magnitude difference between brightest and second brightest component | 0.2 |
| position angle | 6 ° |
sources:
| 2 | HD and HDE Catalogs |
| Cannon, A.J., and E.C. Pickering, Harvard Annals, Vols 91-99, 1918-24, Cambridge, Massachusetts: Harvard University; Cannon, A.J., Harvard Annals, Vol. 100, 1925-36, Cambridge, Massachusetts: Harvard University; and Cannon, A.J., and M. Walton Mayall, Harvard Annals, Vol. 112, 1949, Cambridge, Massachusetts: Harvard University | |
| 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 | |
| 17 | ACRS |
| Corbin, T.E., and S.E. Urban, Astrographic Catalog Reference Stars, United States Naval Observatory, 1991 | |
| 19 | WDS Catalog |
| Worley, C.E., and G.G. Douglass, Washington Catalog of Visual Double Stars 1996.0, United States Naval Observatory, 1996 | |
| 25 | Bright Star Catalogue, 5th edition |
| Hoffleit, D. and Warren, W.H. Jr., The Bright Star Catalogue, 5th Revised Edition, Version 2, 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 (B1950) | RA: 18h 33min 25.444sec | DEC: +23° 33' 49.92'' | ±0.017 arcsec |
| position (J2000) | RA: 18h 35min 30.403sec | DEC: +23° 36' 20.35'' | |
| proper motion B1950 (FK4) | RA: 0.0002 arcsec/a | DEC: 0.006 arcsec/a | ±0.003 arcsec/a in RA ±0.003 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: 0.0003 arcsec/a | DEC: 0.005 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 5.8 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from Harvard or San Luis photometry. |
spectral information:
| spectral class | K0 |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
remarks for duplicity and variability
| Double star in Aitken's Double Star Catalogue (Aitken 1932) |
catalogues
| source catalogue | GC, catalogue number: 25407 |
| Durchmusterung | BD+23 3385 |
| Boss General Catalogue | 25407 |
| Henry Draper Catalogue | 171745 |
data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)
position and proper motion:
| position (J2000) | RA: 18h 35.5min | DEC: +23° 36' |
| proper motion (J2000) | RA: 0.006 arcsec/a | DEC: 0.007 arcsec/a |
double/multiple star system information:
| component | year | number of measures | position angle | angular separation | magnitude of 1st component | magnitude of 2nd component | spectral class(es) | discoverer code |
| - | 1843 | often | 355° | 0.6'' | 6.3 | 6.5 | G9III-IV | STT 359 |
| 1992 | 6° | 0.7'' |
discoverer information:
| discoverer code | discoverer | reference |
| STT 359 | Struve, O. | - |
notes:
| note | P = 211yr., a = 0.42", motion retrograde. Spectrum composite; G9III+G7III. |
data from 4th Catalog of Orbits of Visual Binaries (Worley+, 1983)
position:
| position (B1900) | RA: 18h 31.4min | DEC: +23° 31' |
magnitudes, spectral classes, orbital elements:
| author: | L.S.T. Symms | S. Arend |
| date of observation: | 1963 | |
| magnitude of component A: | 6.3 | 6.3 |
| magnitude of component B: | 6.3 | 6.3 |
| spectral class component B: | G9III | G9III |
| spectral class component B: | G9III | G9III |
| period [y]: | 210.9 | 190.8 |
| semi-major axis [arcsec]: | 0.416 | 0.418 |
| inclination [deg]: | 118.69 | 119.34 |
| node [deg]: | 6.94 | 10.32 |
| equinox of node: | 1900 | |
| eccentricity: | 0.821 | 0.818 |
| time of periastron passage: | 1929.5 | 1932.02 |
| dates of ephemeris: | 1935-1980 | |
| grade: | reliable | reliable |
| reference: | Circ. Inf. No. 33, 1964. | Ann. Obs. R. Bel. 5, 161; 1951. |
| other name(s) | STT 359 |