m2Crucis
| catalogues and names | m2Cru, mu 2 Cru, HR 4899, HD 112091, SAO 240367, WDS 12546-5710B |
| constellation | Crux |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
position, motion, parallax:
| position (J2000) | RA: 12h 54min 36,8sec | DEC: -57° 10' 6'' |
| position (J1900) | RA: 12h 48min 44sec | DEC: -56° 37' 31'' |
| proper motion (J2000) | RA: -0,035 arcsec/a | DEC: -0,001 arcsec/a |
| radial velocity | 19 km/s note: variable radial velocity |
|
| rotational velocity | 201 km/s (uncertain) (variable) | |
magnitude
| visual magnitude | 5,17 (V on UBV Johnson system) |
spectral / color information
| spectral class | B5Vne |
| B-V-magnitude | -0,12 |
| U-B-magnitude | -0,51 |
| R-I-magnitude | -0,06 |
variability information
| variable star identification | Mu2 Cru |
| note (category: variability): | Gamma Cas 4.99 - 5.18V. |
double/multiple star system information
| separation | 34,9 arcsec |
| mag difference (of double or brightest multiple) | 1 |
| note | Worley (1978) update of the IDS |
| note (category: double and multiple data): | CPM with HR 4898. |
miscellaneous information
| note (category: group membership): | Sco-Cen assoc.; probable member of Sco-Cen cluster; member of Pleiades group. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 12h 54min 36,953sec | DEC: -57° 10' 6,55'' | ±0,19 arcsec | source: 16 |
| proper motion (J2000) | RA: -0,0028 arcsec/a | DEC: -0,008 arcsec/a | source: 25 | |
| radial velocity | 19 km/s | source: 25 | ||
| galactic coord. (B1950) | longitude: 303,37° | latitude: 5,7° | ||
| GCI unit vector (J2000) | X: -0,526848 | Y: -0,127983 | Z: -0,840269 | |
magnitude:
| visual | 5,17 (observed) | source: 25 |
| photovisual | 5,5 | source: 2 |
| photographic | 5,3 | source: 2 |
spectral information:
| spectral class | B3p | source: 29 | |
| Morgan-Keenan | B5Vne | source: 25 | |
| B-magnitude | 5,05 ±0,05 | B-V-magnitude | -0,12 |
| U-magnitude | 4,54 ±0,05 | U-B-magnitude | -0,51 |
double/multiple star system information:
| separation between brightest and second brightest component | 34,9 arcsec |
| magnitude difference between brightest and second brightest component | 1,14 |
| position angle | 17 ° |
| component | magnitude | spectral class | catalogue(s)/name(s) |
| A | 4,03 | B3 | m1Crucis, HR 4898, HD 112092, SAO 240366 |
| B | 5,17 | B3p | m2Crucis, HR 4899, HD 112091, SAO 240367 |
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 | |
| 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 | |
| 29 | SAOJ2000 |
| SAO on FK5 at J2000, 1989 | |
data from Smithsonian Astrophysical Observatory Star Catalog (SAO Staff 1966; USNO, ADC 1990)
position and proper motion:
| position (J1950) | RA: 12h 51min 39,615sec | DEC: -56° 53' 49,85'' | ±0,045 arcsec |
| position (J2000) | RA: 12h 54min 36,825sec | DEC: -57° 10' 5,6'' | |
| proper motion J1950 (FK4) | RA: -0,0039 arcsec/a | DEC: -0,005 arcsec/a | ±0,01 arcsec/a in RA ±0,006 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: -0,0043 arcsec/a | DEC: -0,001 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 5,5 (accuracy: 2 decimals) |
| source of visual magnitude data | Taken from Harvard or San Luis photometry. |
spectral information:
| spectral class | B3p |
| 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: 17513 |
| Durchmusterung | CP-56 5487B |
| Boss General Catalogue | 17513 |
| Henry Draper Catalogue | 112091 |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
| position (J1950) | RA: 12h 51min 39,6sec | DEC: -56° 53' 50'' |
variability informations:
| variability type | GCAS | eruptive variable star |
| magnitute at max. brightness | 4,99 | |
| magnitute at min. brightness | 5,18 | |
| photometric system | visual, photovisual or Johnson's V |
spectral information
| spectral class | B5Vne |
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 'Cape Photographic Durchmusterung' |
miscanellous
| ID in the GCVS catalogue | 30/90122 |
| constellation | Crux |
| notes on existence | The star is equivalent to '0310001 R'. |
variability type description
| variability type | description |
| GCAS | Eruptive irregular variables of the Gamma Cas type. These are rapidly rotating B III-IVe stars with mass outflow from their equatorial zones. The formation of equatorial rings or disks is often accompanied by temporary fading. Light amplitudes may reach 1.5 mag in V. |