Xi Ophiuchi

light-years
Proper names: Xi Ophiuchi, 40 Ophiuchi
Catalog numbers:
     Gliese (Gl) 670, Henry Draper (HD) 156897, Bonner Durchmusterung (BD) -20°4731, Hipparcos Input Catalog (HIC) 84893, Smithsonian Astrophysical Observatory (SAO) 185296, Hoffleit Bright Star (HR) 6445, Donner (DON) 832
Heavy element abundance: 74% of Sol
Source for heavy element abundance: Strobel [Fe/H] Determinations
Arity: binary
Right Ascension and Declination: 17h21m0.234s, -21°6'46.26" (epoch 2000.0)
Distance from Sol: 56.7 light-years (17.4 parsecs)
Standard error in distance: 1.5922%
Source for distance: Hipparcos
Celestial (X,Y,Z) coordinates in ly: -8.96, -52.2, -20.4
Galactic (X,Y,Z) coordinates in ly: 56.0, 3.86, 8.20
Proper motion: 0.313 arcsec/yr (132.0° from north)
Radial Velocity: -8.8 km/sec
Source for proper motion and radial velocity: Gliese
Galactic (U,V,W) velocity components in km/s: -4.75, -4.06, -26.5

What do all these fields mean?

Data for A and B's orbit around one other:
Combined absolute visual magnitude: +3.19
Combined visual luminosity: 4.61 x Sol
Observed Separation: 47.0 A.U.s
Year of separation observation: 1931
As seen from A:
     B would appear as magnitude -15.52
As seen from B:
     A would appear as magnitude -20.01

Data for A and B's orbit, take 2:
Observed Separation: 64.4 A.U.s
Year of separation observation: 1959
As seen from A:
     B would appear as magnitude -14.83
As seen from B:
     A would appear as magnitude -19.32


Component A:
Spectral class: F2
Luminosity Class: V
Apparent visual magnitude: +4.41
Absolute visual magnitude: +3.21
Visual luminosity: 4.54 x Sol
Diameter: 1.12 x Sol
Source for diameter: Apparent Diameters and Absolute Radii of Stars (Fracassini+ 1988)
Comfort Zone (visual): 2.13 A.U.s
Angular size of star in sky in CZ: 0.281178 degrees


Component B:
Spectral class: K3
Luminosity Class: V
Apparent visual magnitude: +8.90
Absolute visual magnitude: +7.70
Visual luminosity: 0.073 x Sol
Diameter: 0.7 x Sol
Source for diameter: Apparent Diameters and Absolute Radii of Stars (Fracassini+ 1988)
Comfort Zone (visual): 0.27 A.U.s
Angular size of star in sky in CZ: 1.385033 degrees

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