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. The Washington Visual Double Star Catalog, 1996.0

catalogues and names Sirius, a CMa, NSV 17173, 9 CMa, HR 2491, HD 48915, SAO 151881, FK5: 257, WDS 06451-1643A
other names Canicula, Dog Star, Aschere
constellation Canis Major

data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)

note (category: star names): SIRIUS; Canicula; Dog Star; Aschere.

object is infrared source (NASA merged infrared catalogue, Schmitz et al., 1978)

position, motion, parallax:

position (J2000) RA: 6h 45min 8,9sec DEC: -16 42' 58''
position (J1900) RA: 6h 40min 44,6sec DEC: -16 34' 44''
proper motion (J2000) RA: -0,553 arcsec/a DEC: -1,205 arcsec/a
radial velocity -8 km/s
note: spectroscopic binaries
note: orbital data avaible
rotational velocity 13 km/s (uncertain) (variable)
trigonometric parallax 0,375 arcsec
note (category: dynamical parallaxes): 0.376".


visual magnitude -1,46
(V on UBV Johnson system)

spectral / color information

spectral class A1Vm
B-V-magnitude 0
U-B-magnitude -0,05
R-I-magnitude -0,03
note (category: spectra): Cadmium discovered in spectra from COPERNICUS. Iron overabundant by a factor of 5 in comparison with Sun and titanium by a factor of 2. Possibility that the atmosphere of Sirius A polluted by material ejected from Sirius B. Weak magnetic field. Barium abundance greater than solar abundance by about 1.76. Also classified A/A0/A1.
note (category: colors): Color excess E(B-V) = -0.03.

double/multiple star system information

number of components of multiple star system 4
separation 11,2 arcsec
mag difference (of double or brightest multiple) 10,3
component ID AB
note (category: double and multiple data): AB -1.46 A1V, 8.49 A1V, 50.090y, a = 7.500" or 49.94y, a = 7.62". D, 14.0v at 32" from A. C, companion to B at 1.4" suspected but not confirmed. B is first white dwarf ever discovered; predicted by Bessel (1844) on basis of orbital motion of Sirius, it was first seen by Alvan Clark in 1862, and its peculiar high temperature, small size and great density established by W. Adams in 1925.
note (category: spectroscopic binaries): 50.04y D, K 2.4k/s, V0 -7.6k/s, asini 487.

miscellaneous information

note (category: group membership): Sirius group; UMa stream.
note (category: stellar radii or diameters): Diam. = 0.00560 - 0.00589".
note (category: miscellaneous): Soft X-rays observed from Astronomical Netherlands Satellite (ANS). Sirius B not unusual compared with other dA white dwarfs. Effective temperature about 32000K.

data from SKY2000 - Master Star Catalog (Myers+ 1997)

position, motion, parallax:

position (J2000) RA: 6h 45min 8,821sec DEC: -16 42' 56,85'' 0,06 arcsec source: 15
proper motion (J2000) RA: -0,0385 arcsec/a DEC: -1,205 arcsec/a source: 25
radial velocity -8 km/s source: 25
trigonometric parallax 0,375 0,037 arcsec source: 25
galactic coord. (B1950) longitude: 227,22 latitude: -8,88
GCI unit vector (J2000) X: -0,187449 Y: 0,93922 Z: -0,287625


visual -1,46 (observed) source: 25
photovisual -1,6 source: 2
photographic -1,6 source: 2

spectral information:

spectral class A0 source: 96
Morgan-Keenan A1Vm source: 25
B-magnitude -1,46 0,05 B-V-magnitude 0
U-magnitude -1,51 0,05 U-B-magnitude -0,05

double/multiple star system information:

source of data: 19
magnitude difference between brightest and second brightest component 10


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
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
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: 6h 42min 56,713sec DEC: -16 38' 46,37'' 0,003 arcsec
position (J2000) RA: 6h 45min 8,917sec DEC: -16 42' 58,11''
proper motion J1950 (FK4) RA: -0,0379 arcsec/a DEC: -1,211 arcsec/a 0,001 arcsec/a in RA
0,001 arcsec/a in DEC
proper motion J2000 (FK5) RA: -0,0379 arcsec/a DEC: -1,206 arcsec/a
source of proper motion data Determined by source catalog


visual -1,6 (accuracy: 2 decimals)
source of visual magnitude data Combined magnitude of component stars.

spectral information:

spectral class A0
source of spectral data Taken from the Henry Draper Catalogue or no spectrum in source catalog.

remarks for duplicity and variability

Double star - see source catalog for source


source catalogue FK4, catalogue number: 257
Durchmusterung BD-16 1591
Boss General Catalogue 8833
Henry Draper Catalogue 48915

data from The Washington Visual Double Star Catalog, 1996.0 (Worley+, 1996)

position and proper motion:

position (J2000) RA: 6h 45,1min DEC: -16 43'
proper motion (J2000) RA: -0,553 arcsec/a DEC: 0 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 1861 often '' -1,46 8,5 A1Vm AGC 1
AD 1865 2 170 44,3'' - 14 A0 AGC 1
1915 183 31,6''
AE 1877 1 115 71,4'' - - - HL 3
AF 1877 4 159 103,7'' - - - BU 1411
BC 1920 7 69 1,8'' - - - AGC 1
1929 129 1,4''

discoverer information:

discoverer code discoverer reference
AGC 1 - -
HL 3 Hall, A. -
BU 1411 Burnham, S.W. -


note AB: Sirius. Magnitude of A -1.58. Proper motion of A -553 -1205. P = 50.1yr., a = 7.50", motion retrograde. BC: Suspected by Fox in 1920, also reported by Innes, van den Bos, and Finsen. Oother observers fail to confirm duplicity of B. Single 1945, 1946, 1949, 1950.