Spica

light-years
Proper names: Spica, Alpha Virginis, 67 Virginis, The Ear of Wheat, Al Simak al A'zal
Catalog numbers:
     Henry Draper (HD) 116658, Bonner Durchmusterung (BD) -10°3672, Hoffleit Bright Star (HR) 5056, Smithsonian Astrophysical Observatory (SAO) 157923, Fifth Fundamental Catalogue (FK5) 498, Hipparcos Input Catalog (HIC) 65474, Caltech 2-microns Survey (IRC) -10286
Arity: binary
Right Ascension and Declination: 13h25m11.587s, -11°9'40.71" (epoch 2000.0)
Distance from Sol: 262 light-years (80.4 parsecs)
Standard error in distance: 6.4662%
Source for distance: Hipparcos
Celestial (X,Y,Z) coordinates in ly: -240, -93.4, -50.8
Galactic (X,Y,Z) coordinates in ly: 122, -114, 202
Proper motion: 0.0496 arcsec/yr (235.7° from north)
Radial Velocity: 1 km/sec
Source for proper motion and radial velocity: Hipparcos Input Catalog
Galactic (U,V,W) velocity components in km/s: -7.58, -17.0, -3.67

What do all these fields mean?

Data for A and B's orbit around one other:
Combined absolute visual magnitude: -3.72
Combined visual luminosity: 2684 x Sol
Period: 4.01416 days
Semimajor Axis: 0.12 A.U.s
Eccentricity: 0.1
Periastron distance: 0.108 A.U.s
Apastron distance: 0.132 A.U.s
Source for orbit data: Burnham's Celestial Handbook
Comfort Zone (visual) around both: 51.8 A.U.s
As seen from A:
     At periastron, B would appear as magnitude -38.43
     At apastron, B would appear as magnitude -38.00
As seen from B:
     At periastron, A would appear as magnitude -39.87
     At apastron, A would appear as magnitude -39.44


Component A:
Spectral class: B1
Luminosity Class: V
Apparent visual magnitude: +1.06 (increasing to +0.86)
Absolute visual magnitude: -3.47 (increasing to -3.67)
Visual luminosity: 2121 x Sol (increasing to 2550 x Sol)
Variable type: rotating ellipsoidal (rotating variable)
Period of variability: 4.176 hours
Color indices: B-V= -0.23
Mass: 10.9 x Sol
Source for mass: Burnham's Celestial Handbook
Diameter: 7.34 x Sol
Source for diameter: Apparent Diameters and Absolute Radii of Stars (Fracassini+ 1988)
Comfort Zone (visual): 46.1 A.U.s
Orbital period in CZ: 94.6624 years
Tidal index in CZ: 0.000112
Angular size of star in sky in CZ: 0.085008 degrees


Component B:
Spectral class: B7
Luminosity Class: V
Apparent visual magnitude: +2.50
Absolute visual magnitude: -2.03
Visual luminosity: 563 x Sol
Mass: 6.8 x Sol
Source for mass: Burnham's Celestial Handbook
Diameter: 4 x Sol
Comfort Zone (visual): 23.7 A.U.s
Orbital period in CZ: 44.3216 years
Tidal index in CZ: 0.000509
Angular size of star in sky in CZ: 0.089873 degrees

light-years
but not more than light-years away
Data for this star system were most recently updated on 4-April-2001.