Metallah
| catalogues and names | Metallah, a Tri, alf Tri, 2 Tri, HR 544, HD 11443, SAO 74996, FK5: 64, WDS 01531+2935A |
| other names | Mothallah, Atria, Caput Trianguli, Ras al Muthallah, Elmuthalleth |
| constellation | Triangulum |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
| note (category: star names): | Metallah; Mothallah; Atria; Caput Trianguli; Ras al Muthallah; Elmuthalleth. |
position, motion, parallax:
| position (J2000) | RA: 1h 53min 4,9sec | DEC: +29° 34' 44'' |
| position (J1900) | RA: 1h 47min 22,7sec | DEC: +29° 5' 30'' |
| proper motion (J2000) | RA: 0,011 arcsec/a | DEC: -0,235 arcsec/a |
| radial velocity | -13 km/s note: spectroscopic binaries, single lined spectra note: orbital data avaible |
|
| rotational velocity | 93 km/s (uncertain) (variable) | |
| trigonometric parallax | 0,057 arcsec | |
magnitude
| visual magnitude | 3,41 (V on UBV Johnson system) |
spectral / color information
| spectral class | F6IV |
| B-V-magnitude | 0,49 |
| U-B-magnitude | 0,06 |
| R-I-magnitude | 0,28 |
double/multiple star system information
| number of components of multiple star system | 3 |
| separation | 222,3 arcsec |
| mag difference (of double or brightest multiple) | 8,6 |
| component ID | AC |
| note | Worley (1978) update of the IDS |
| note (category: double and multiple data): | Visual companions probably optical. |
| note (category: spectroscopic binaries): | 1.7365d, K 12.4k/s, V0 -20.0k/s, asini 0.296. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 1h 53min 4,905sec | DEC: +29° 34' 43,82'' | ±0,06 arcsec | source: 15 |
| proper motion (J2000) | RA: 0,0009 arcsec/a | DEC: -0,235 arcsec/a | source: 25 | |
| radial velocity | -13 km/s | source: 25 | ||
| trigonometric parallax | 0,057 | ±0,006 arcsec | source: 25 | |
| galactic coord. (B1950) | longitude: 138,65° | latitude: -31,4° | ||
| GCI unit vector (J2000) | X: 0,765944 | Y: 0,411909 | Z: 0,493621 | |
magnitude:
| visual | 3,41 (observed) | source: 25 |
| photovisual | 3,6 | source: 2 |
spectral information:
| spectral class | F5 | source: 96 | |
| Morgan-Keenan | F6IV | source: 25 | |
| B-magnitude | 3,9 ±0,05 | B-V-magnitude | 0,49 |
| U-magnitude | 3,96 ±0,05 | U-B-magnitude | 0,06 |
double/multiple star system information:
| separation between brightest and second brightest component | 85 arcsec |
| magnitude difference between brightest and second brightest component | 9,5 |
| position angle | 309 ° |
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: 1h 50min 13,44sec | DEC: +29° 20' 10,14'' | ±0,004 arcsec |
| position (J2000) | RA: 1h 53min 4,899sec | DEC: +29° 34' 43,94'' | |
| proper motion J1950 (FK4) | RA: 0,0008 arcsec/a | DEC: -0,229 arcsec/a | ±0,001 arcsec/a in RA ±0,001 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: 0,0008 arcsec/a | DEC: -0,234 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 3,6 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from the "Henry Draper Catalogue". |
spectral information:
| spectral class | F5 |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
| source catalogue | FK4, catalogue number: 64 |
| Durchmusterung | BD+28 312 |
| Boss General Catalogue | 2272 |
| Henry Draper Catalogue | 11443 |
data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)
position and proper motion:
| position (J2000) | RA: 1h 53,1min | DEC: +29° 35' |
| proper motion (J2000) | RA: 0,011 arcsec/a | DEC: -0,235 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 | 1879 | 2 | 304° | 80,6'' | 3,41 | 12,9 | F6IV | BUP 27 |
| 1909 | 309° | 85'' | ||||||
| AC | 1879 | 2 | 182° | 228,3'' | 3,41 | 12,2 | F6IV | BUP 27 |
| 1909 | - | 222,3'' | ||||||
| AD | 1879 | 1 | 173° | 308,3'' | 3,41 | 10,5 | F6IV | BUP 27 |
discoverer information:
| discoverer code | discoverer | reference |
| BUP 27 | - | - |
notes:
| note | Alpha Tri. A is a spectroscopic binary, P = 1.77d. |