d Crucis
catalogues and names | d Cru, del Cru, HR 4656, HD 106490, SAO 239791, FK5: 455 |
constellation | Crux |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
position, motion, parallax:
position (J2000) | RA: 12h 15min 8,7sec | DEC: -58° 44' 56'' |
position (J1900) | RA: 12h 9min 49,9sec | DEC: -58° 11' 33'' |
proper motion (J2000) | RA: -0,041 arcsec/a | DEC: -0,009 arcsec/a |
radial velocity | 22 km/s note: suspected variable radial velocity |
|
rotational velocity | 194 km/s (uncertain) (variable) | |
trigonometric parallax | 0,003 arcsec |
magnitude
visual magnitude | 2,8 (V on UBV Johnson system) |
spectral / color information
spectral class | B2IV |
B-V-magnitude | -0,23 |
U-B-magnitude | -0,91 |
R-I-magnitude | -0,24 |
variability information
variable star identification | Del Cru |
note (category: variability): | Beta C 2.78 - 2.84V, 2.25 - 2.31p, 0.151038d. Expanding circumstellar shell. |
miscellaneous information
note (category: group membership): | Probable member of Sco-Cen cluster; lower Cen group of Sco-Cen assoc. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
position (J2000) | RA: 12h 15min 8,683sec | DEC: -58° 44' 56,08'' | ±0,06 arcsec | source: 15 |
proper motion (J2000) | RA: -0,0053 arcsec/a | DEC: -0,009 arcsec/a | source: 25 | |
radial velocity | 22 km/s | source: 25 | ||
trigonometric parallax | 0,003 | - | source: 25 | |
galactic coord. (B1950) | longitude: 298,23° | latitude: 3,79° | ||
GCI unit vector (J2000) | X: -0,517657 | Y: -0,034257 | Z: -0,854902 |
magnitude:
visual | 2,78 (observed) | source: 30 |
photovisual | 3,1 | source: 2 |
photographic | 2,9 | source: 2 |
spectral information:
spectral class | B3 | source: 96 | |
Morgan-Keenan | B2IV | source: 25 | |
B-magnitude | 2,57 ±0,05 | B-V-magnitude | -0,23 |
U-magnitude | 1,66 ±0,05 | U-B-magnitude | -0,91 |
variability information:
variability type | 140 |
var. amplitude | 0,06 |
var. period | 0,15 |
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 | |
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: 12h 12min 28,6sec | DEC: -58° 28' 14,8'' | ±0,009 arcsec |
position (J2000) | RA: 12h 15min 8,675sec | DEC: -58° 44' 55,81'' | |
proper motion J1950 (FK4) | RA: -0,0049 arcsec/a | DEC: -0,01 arcsec/a | ±0,002 arcsec/a in RA ±0,002 arcsec/a in DEC |
proper motion J2000 (FK5) | RA: -0,0053 arcsec/a | DEC: -0,006 arcsec/a | |
source of proper motion data | Determined by source catalog |
magnitude:
visual | 3,1 (accuracy: 2 decimals) |
source of visual magnitude data | Taken from the "Henry Draper Catalogue". |
spectral information:
spectral class | B3 |
source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
catalogues
source catalogue | FK4, catalogue number: 455 |
Durchmusterung | CP-58 4189 |
Boss General Catalogue | 16724 |
Henry Draper Catalogue | 106490 |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
position (J1950) | RA: 12h 12min 28,6sec | DEC: -58° 28' 15'' |
variability informations:
variability type | BCEP | pulsating variable star |
magnitute at max. brightness | 2,78 | |
magnitute at min. brightness | 2,84 | |
photometric system | visual, photovisual or Johnson's V | |
period [d] | 0,151038 | |
rising time | 40 % of period |
spectral information
spectral class | B2IV |
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 | 30/9004 |
constellation | Crux |
notes on existence | The star is equivalent to '03090082tet 2'. |
variability type description
variability type | description |
BCEP | Variables of the Beta Cephei type (Beta Cep, Beta CMa), which are pulsating O8-B6 I-V stars with periods of light and radial-velocity variations in the range of 0.1 - 0.6 days and light amplitudes from 0.01 to 0.3 mag in V. The light curves are similar in shape to average radial-velocity curves but lag in phase by a quarter of the period, so that maximum brightness corresponds to maximum contraction, i.e., to minimum stellar radius. The majority of these stars probably show radial pulsations, but some (V649 Per) display nonradial pulsations; multiperiodicity is characteristic of many of these stars. |