m2Crucis


The object was found in the following catalogues:
  1. The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version)

  2. SKY2000 - Master Star Catalog

  3. Smithsonian Astrophysical Observatory Star Catalog

  4. Combined General Catalogue of Variable Stars (Vol. I-III)


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:

source of data: 19
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.