Mesarthim
| catalogues and names | Mesarthim, g2Ari, gam Ari, 5 Ari, HR 546, HD 11502, SAO 92681, WDS 01535+1918A |
| other names | Mesartim, First Star in Aries |
| constellation | Aries |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
| note (category: star names): | Mesarthim; Mesartim; "First Star in Aries". |
position, motion, parallax:
| position (J2000) | RA: 1h 53min 31,8sec | DEC: +19° 17' 37'' |
| position (J1900) | RA: 1h 48min 2,4sec | DEC: +18° 48' 13'' |
| proper motion (J2000) | RA: 0,079 arcsec/a | DEC: -0,104 arcsec/a |
| radial velocity | -1 km/s note: variable radial velocity |
|
| rotational velocity | 63 km/s (uncertain) (variable) | |
| trigonometric parallax | 0,026 arcsec | |
| note (category: dynamical parallaxes): | 0.019". |
magnitude
| visual magnitude | 4,75 (original HR magnitude) |
spectral / color information
| spectral class | A1pSi |
| B-V-magnitude | -0,04 |
| U-B-magnitude | -0,13 |
| R-I-magnitude | -0,05 |
| note (category: spectra): | Also classified A0pCr, A1pCrSiSr. |
variability information
| variable star identification | Gam Ari |
| note (category: variability): | Alpha CV 3.88 - 3.90V, 2.6095 or 1.7982d; also possibly 2.5 hrs., amp. 0.02, unconfirmed. Southern component of ADS 1507. Magnetic var. |
double/multiple star system information
| number of components of multiple star system | 3 |
| separation | 7,8 arcsec |
| mag difference (of double or brightest multiple) | 0,1 |
| component ID | AB |
| note (category: double and multiple data): | Binary with HR 545, orbital period 5000 - 10000y? Component C, 9.6v at 221". Combined colors for HR 545-6; combined mag. 3.88V. |
miscellaneous information
| note (category: group membership): | Pleiades group. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 1h 53min 31,825sec | DEC: +19° 17' 37,21'' | ±1,24 arcsec | source: 29 |
| proper motion (J2000) | RA: 0,0056 arcsec/a | DEC: -0,104 arcsec/a | source: 25 | |
| radial velocity | -1 km/s | source: 25 | ||
| trigonometric parallax | 0,026 | ±0,003 arcsec | source: 25 | |
| galactic coord. (B1950) | longitude: 142,56° | latitude: -41,2° | ||
| GCI unit vector (J2000) | X: 0,830382 | Y: 0,44866 | Z: 0,33041 | |
magnitude:
| visual | 4,75 (observed) | source: 51 |
| photovisual | 4,8 | source: 2 |
| photographic | 4,8 | source: 2 |
spectral information:
| Morgan-Keenan | A1pSi | source: 25 | |
| B-magnitude | 4,71 ±0,05 | B-V-magnitude | -0,04 |
| U-magnitude | 4,58 ±0,05 | U-B-magnitude | -0,13 |
variability information:
| variability type | 160 |
| var. amplitude | 0 |
| var. period | 2,61 |
| var. epoch | 2440998,99 16. February 1971, 11:45:36 UT |
| next max light | 2451616,47 12. March 2000, 23:16:48 UT |
double/multiple star system information:
| separation between brightest and second brightest component | 7,5 arcsec |
| magnitude difference between brightest and second brightest component | 0 |
| position angle | 0 ° |
| component | magnitude | spectral class | catalogue(s)/name(s) |
| A | 4,75 | - | Mesarthim, g2Arietis, 5 Ari, HR 546, HD 11502, SAO 92681 |
| B | 4,83 | A0 | g1Arietis, 5 Ari, HR 545, HD 11503, SAO 92680 |
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 | |
| 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 | |
| 27 | Catalog of Red Magnitudes (CRM) |
| Warren, W.H. Jr., Northern Hemisphere Catalog of Red Magnitudes, 1994 | |
| 29 | SAOJ2000 |
| SAO on FK5 at J2000, 1989 | |
| 51 | Harvard photometry |
| "H" coded (Harvard photometry) magnitudes from the BSC5. | |
data from Smithsonian Astrophysical Observatory Star Catalog (SAO Staff 1966; USNO, ADC 1990)
position and proper motion:
| position (J1950) | RA: 1h 50min 46,872sec | DEC: +19° 2' 57,87'' | ±0,014 arcsec |
| position (J2000) | RA: 1h 53min 31,825sec | DEC: +19° 17' 37,21'' | |
| proper motion J1950 (FK4) | RA: 0,0056 arcsec/a | DEC: -0,1 arcsec/a | ±0,002 arcsec/a in RA ±0,002 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: 0,0056 arcsec/a | DEC: -0,104 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 4,8 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from Harvard or San Luis photometry. |
spectral information:
| spectral class | A0p |
| 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: 2291 |
| Durchmusterung | BD+18 243A |
| Boss General Catalogue | 2291 |
| Henry Draper Catalogue | 11503 |
data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)
position and proper motion:
| position (J2000) | RA: 1h 53,5min | DEC: +19° 18' |
| proper motion (J2000) | RA: 0,081 arcsec/a | DEC: -0,108 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 | 1821 | often | 358° | 8,6'' | 4,8 | 4,8 | A1pSi B9V | STF 180 |
| 1988 | 0° | 7,5'' | ||||||
| AC | 1823 | 8 | 85° | 228,8'' | 4,8 | 9,6 | - | STF 180 |
| 1924 | 84° | 221,3'' |
discoverer information:
| discoverer code | discoverer | reference |
| STF 180 | Struve, F.G.W. | - |
notes:
| note | Gamma Ari. A is a variable of the Alpha CVn type. Proper motion of B +077 -115. |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
| position (J1950) | RA: 1h 50min 46,9sec | DEC: +19° 2' 58'' |
variability informations:
| variability type | ACV | rotating variable star |
| magnitute at max. brightness | 4,62 | |
| magnitute amplitude | 0,04 | |
| photometric system | visual, photovisual or Johnson's V | |
| epoch for maximum light [JD] | 2440998,99 16. February 1971, 11:45:36 UT |
|
| period [d] | 2,6095 | |
| next maximum light [JD] | 2451617,0455 13. March 2000, 13:05:31 UT |
|
| rising time | 50 % of period |
spectral information
| spectral class | A1p(Cr-Si-Sr) |
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 | 7/9003 |
| constellation | Aries |
| notes on existence | The star is equivalent to '0080001 R'. |
| There are notes in published catalog. | |
variability type description
| variability type | description |
| ACV | Alpha2 Canum Venaticorum variables. These are main-sequence stars with spectral types B8p-A7p and displaying strong magnetic fields. Spectra show abnormally strong lines of Si, Sr, Cr, and rare earths whose intensities vary with rotation. They exhibit magnetic field and brightness changes (periods of 0.5-160 days or more). The amplitudes of the brightness changes are usually withine 0.01-0.1 mag in V. ACVO Rapidly oscillating Alpha2 CVn variables. These are nonradially pulsating, rotating magnetic variables of Ap spectral type (DO Eri). Pulsation periods are in the range of 6-12 mmag (0.004-0.01 days), while amplitudes of light variation caused by the pulsation are about 0.01 mag in V. The pulsational variations are superposed on those caused by rotation. |