Menkar
| catalogues and names | Menkar, a Cet, alf Cet, 92 Cet, HR 911, HD 18884, SAO 110920, FK5: 107 |
| other names | Mekab, Menkab, Monkar |
| constellation | Cetus |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
| note (category: star names): | MENKAR; Mekab; Menkab; Monkar. |
position, motion, parallax:
| position (J2000) | RA: 3h 2min 16,8sec | DEC: +4° 5' 23'' |
| position (J1900) | RA: 2h 57min 3sec | DEC: +3° 41' 51'' |
| proper motion (J2000) | RA: -0,009 arcsec/a | DEC: -0,078 arcsec/a |
| radial velocity | -26 km/s note: variable radial velocity |
|
| trigonometric parallax | 0,009 arcsec | |
magnitude
| visual magnitude | 2,53 (V on UBV Johnson system) |
spectral / color information
| spectral class | M1.5IIIa |
| B-V-magnitude | 1,64 |
| U-B-magnitude | 1,94 |
| R-I-magnitude | 1,16 |
| note (category: spectra): | Ultraviolet FeII emission. |
variability information
| variable star identification | Alp Cet |
| note (category: variability): | Lb? 2.45 - 2.54V. Spectrum var. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 3h 2min 16,773sec | DEC: +4° 5' 22,93'' | ±0,06 arcsec | source: 15 |
| proper motion (J2000) | RA: -0,0006 arcsec/a | DEC: -0,078 arcsec/a | source: 25 | |
| radial velocity | -26 km/s | source: 25 | ||
| trigonometric parallax | 0,009 | ±0,001 arcsec | source: 25 | |
| galactic coord. (B1950) | longitude: 173,32° | latitude: -45,59° | ||
| GCI unit vector (J2000) | X: 0,698256 | Y: 0,712286 | Z: 0,071318 | |
magnitude:
| visual | 2,4 (observed) | source: 31 |
| photovisual | 2,8 | source: 2 |
spectral information:
| spectral class | M0 | source: 96 | |
| Morgan-Keenan | M1.5IIIa | source: 25 | |
| B-magnitude | 4,17 ±0,05 | B-V-magnitude | 1,64 |
| U-magnitude | 6,11 ±0,05 | U-B-magnitude | 1,94 |
variability information:
| variability type | 171 |
| var. amplitude | 0,09 |
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 | |
| 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 | |
| 31 | CRM' (non-GCVS variable data) |
| Warren, W.H. Jr., Northern Hemisphere Catalog of Red Magnitudes, 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: 2h 59min 39,744sec | DEC: +3° 53' 41,15'' | ±0,003 arcsec |
| position (J2000) | RA: 3h 2min 16,777sec | DEC: +4° 5' 22,93'' | |
| proper motion J1950 (FK4) | RA: -0,0008 arcsec/a | DEC: -0,074 arcsec/a | ±0,001 arcsec/a in RA ±0,001 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: -0,0006 arcsec/a | DEC: -0,078 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 2,8 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from the "Henry Draper Catalogue". |
spectral information:
| spectral class | M0 |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
| source catalogue | FK4, catalogue number: 107 |
| Durchmusterung | BD+03 419 |
| Boss General Catalogue | 3643 |
| Henry Draper Catalogue | 18884 |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
| position (J1950) | RA: 2h 59min 39,7sec | DEC: +3° 53' 41'' |
variability informations:
| variability type | LB: | pulsating variable star |
| magnitute at max. brightness | 2,45 | |
| magnitute at min. brightness | 2,54 | |
| photometric system | visual, photovisual or Johnson's V |
spectral information
| spectral class | M2III |
references
| to a study | Vol. I GCVS (see Kholopov et al. 1985-1988) |
| to a chart/photograph | no chart is avaible, but the star is contained in the 'Bonner Durchmusterung' |
miscanellous
| ID in the GCVS catalogue | 21/9001 |
| constellation | Cetus |
| notes on existence | The star is equivalent to '0219004 del'. |
variability type description
| variability type | description |
| LB | Slow irregular variables. The light variations of these stars show no evidence of periodicity, or any periodicity present is very poorly defined and appears only occasionally. Like for the type I, stars are often attributed to this type because of being insufficiently studied. Many type L variables are really semiregulars or belong to other types. LB Slow irregular variables of late spectral types (K, M, C, S); as a rule, they are giants (CO Cyg). This type is also ascribed, in the GCVS, to slow red irregular variables in the case of unknown spectral types and luminosities. LC Irregular variable supergiants of late spectral types having amplitudes of about 1 mag in V (TZ Cas). |