Sigma Boötis

light-years
Proper names: Sigma Boötis, 28 Boötis, Sigma Bootis, 28 Bootis
Catalog numbers:
     Gliese (Gl) 557, Henry Draper (HD) 128167, Bonner Durchmusterung (BD) +30°2536, Hipparcos Input Catalog (HIC) 71284, Smithsonian Astrophysical Observatory (SAO) 83416, Fifth Fundamental Catalogue (FK5) 1380, Hoffleit Bright Star (HR) 5447, New Suspected Variable (NSV) 6717
Age: 2100 million years
Source for age: B. Edvardsson et al., "Chemical Evolution of the Galactic Disc", A&AP 275
Heavy element abundance: 45% of Sol
Standard error in heavy element abundance: 23%
Source for heavy element abundance: Strobel [Fe/H] Determinations
Arity: singular
Right Ascension and Declination: 14h34m40.82s, +29°44'42.46" (epoch 2000.0)
Distance from Sol: 50.4 light-years (15.5 parsecs)
Standard error in distance: 1.1013%
Source for distance: Hipparcos
Celestial (X,Y,Z) coordinates in ly: -34.2, -27.4, 25.0
Galactic (X,Y,Z) coordinates in ly: 14.1, 14.1, 46.3
Proper motion: 0.227 arcsec/yr (55.6° from north)
Radial Velocity: 0.9 km/sec
Source for proper motion and radial velocity: Gliese
Galactic (U,V,W) velocity components in km/s: 2.30, 15.9, -4.55

What do all these fields mean?


Spectral class: F2
Luminosity Class: V
Apparent visual magnitude: +4.46
Absolute visual magnitude: +3.52
Visual luminosity: 3.41 x Sol
Color indices: B-V= +0.36, U-B= -0.08
Diameter: 1.20 x Sol
Source for diameter: Apparent Diameters and Absolute Radii of Stars (Fracassini+ 1988)
Comfort Zone (visual): 1.85 A.U.s
Angular size of star in sky in CZ: 0.345496 degrees

light-years
but not more than light-years away
Data for this star system were most recently updated on 12-May-2001.