Nair al Saif
| catalogues and names | Nair al Saif, i Ori, 44 Ori, HR 1899, HD 37043, SAO 132323, FK5: 209, WDS 05354-0555A |
| other names | Hatysa in Becvar |
| constellation | Orion |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
| note (category: star names): | Nair al Saif; Hatysa in Becvar. |
position, motion, parallax:
| position (J2000) | RA: 5h 35min 26sec | DEC: -5° 54' 36'' |
| position (J1900) | RA: 5h 30min 32,4sec | DEC: -5° 58' 32'' |
| proper motion (J2000) | RA: 0 arcsec/a | DEC: 0,001 arcsec/a |
| radial velocity | 22 km/s note: spectroscopic binaries, double lined spectra note: orbital data avaible |
|
| rotational velocity | 130 km/s (uncertain) (variable) | |
| trigonometric parallax | 0,025 arcsec | |
| note (category: radial and/or rotational velocities): | ADS 4193A, mass ejection vel. up to 1600k/s. ADS 4193B, +16k/s. |
| note (category: dynamical parallaxes): | 0.005". |
magnitude
| visual magnitude | 2,77 (V on UBV Johnson system) |
spectral / color information
| spectral class | O9III |
| B-V-magnitude | -0,24 |
| U-B-magnitude | -1,08 |
| R-I-magnitude | -0,2 |
| note (category: spectra): | Enhanced ultraviolet emission. Helium weak. Interstellar Lyman alpha absorption observed by AEROBEE rocket. Iota Ori B is a helium weak star. Helium deficient by factor of 10 relative to standard stars. P and Ga enormously enhanced. uv 1240 absorption strong; weak 1548. |
| note (category: colors): | Color excess E(B-V) = +0.07. |
variability information
| variable star identification | 2334 |
| note (category: variability): | Component B is NSV 2334, 7.4V. |
double/multiple star system information
| number of components of multiple star system | 3 |
| separation | 11,4 arcsec |
| mag difference (of double or brightest multiple) | 4,5 |
| component ID | AB |
| note (category: double and multiple data): | AB fixed. B is B7IV; vsini 50k/s. |
| note (category: spectroscopic binaries): | ADS 4193A, 29.1351d, K 115.2k/s, V0 +26.6k/s, msin3i 15.7, asini 30.0. |
miscellaneous information
| note (category: group membership): | Iota Ori cluster; Ori OB1c4; sword of Orion; HII region. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 5h 35min 25,974sec | DEC: -5° 54' 35,61'' | ±0,06 arcsec | source: 15 |
| proper motion (J2000) | RA: 0 arcsec/a | DEC: 0,001 arcsec/a | source: 25 | |
| radial velocity | 22 km/s | source: 25 | ||
| trigonometric parallax | 0,025 | ±0,002 arcsec | source: 25 | |
| galactic coord. (B1950) | longitude: 209,53° | latitude: -19,58° | ||
| GCI unit vector (J2000) | X: 0,10642 | Y: 0,988976 | Z: -0,102964 | |
magnitude:
| visual | 2,77 (observed) | source: 25 |
| photovisual | 2,9 | source: 2 |
spectral information:
| spectral class | O0 | source: 96 | |
| Morgan-Keenan | O9III | source: 25 | |
| B-magnitude | 2,53 ±0,05 | B-V-magnitude | -0,24 |
| U-magnitude | 1,45 ±0,05 | U-B-magnitude | -1,08 |
double/multiple star system information:
| separation between brightest and second brightest component | 11,4 arcsec |
| magnitude difference between brightest and second brightest component | 4,1 |
| position angle | 141 ° |
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 | |
| 15 | FK5, FK5 Extension and FK5 Supplement |
| Fricke, W., H. Schwan and T. Lederle, "Fifth Fundamental Catalogue (FK5), Part I. The Basic Fundamental Stars," Veroff. Astronomisches Recheninstitut, No. 32, Heidelberg, Germany, 1988, and Fricke, W., H. Schwan, and T.E. Corbin, "Fifth Fundamental Catalogue (FK5), Part II. The FK5 Extension," Veröff. Astronomisches Recheninstitut, No. 33, Heidelberg, Germany, 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 (J1950) | RA: 5h 32min 59,126sec | DEC: -5° 56' 28,26'' | ±0,006 arcsec |
| position (J2000) | RA: 5h 35min 25,982sec | DEC: -5° 54' 35,6'' | |
| proper motion J1950 (FK4) | RA: -0,0003 arcsec/a | DEC: 0,001 arcsec/a | ±0,001 arcsec/a in RA ±0,001 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: 0,0001 arcsec/a | DEC: 0,001 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 2,9 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from the "Henry Draper Catalogue". |
spectral information:
| spectral class | Oe5 |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
| source catalogue | FK4, catalogue number: 209 |
| Durchmusterung | BD-06 1241 |
| Boss General Catalogue | 6937 |
| Henry Draper Catalogue | 37043 |
data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)
position and proper motion:
| position (J2000) | RA: 5h 35,4min | DEC: -5° 55' |
| proper motion (J2000) | RA: 0 arcsec/a | DEC: 0,001 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 |
| AB | 1831 | 40 | 141° | 11,4'' | 2,9 | 7 | O9III | STF 752 |
| AC | 1824 | 3 | 103° | 49,5'' | 2,9 | - | - | STF 752 |
| BC | 1901 | 1 | 92° | '' | - | - | - | STF 752 |
discoverer information:
| discoverer code | discoverer | reference |
| STF 752 | Struve, F.G.W. | - |
notes:
| note | Iota Ori. A is a spectroscopic binary, P = 29.1d. |