Bonner Durchmusterung +21°4747

light-years

Catalog numbers:
     Gliese (Gl) 857.1, Bonner Durchmusterung (BD) +21°4747, Giclas (G) 127-28, Hipparcos Input Catalog (HIC) 110640, Smithsonian Astrophysical Observatory (SAO) 90482, Aitken Double Star (ADS) 15915, Vyssotsky McCormick (McC) 75, Woolley (Wo) 9781
Arity: binary
Right Ascension and Declination: 22h24m45.55s, +22°33'4.02" (epoch 2000.0)
Distance from Sol: 69.8 light-years (21.4 parsecs)
Standard error in distance: 3.4298%
Source for distance: Hipparcos
Celestial (X,Y,Z) coordinates in ly: 59.0, -26.0, 26.8
Galactic (X,Y,Z) coordinates in ly: 5.80, 60.7, -33.9
Proper motion: 0.2 arcsec/yr (244.3° from north)
Radial Velocity: -6.3 km/sec
Source for proper motion and radial velocity: Gliese
Galactic (U,V,W) velocity components in km/s: 19.5, -5.50, 6.46

What do all these fields mean?

Data for A and B's orbit around one other:
Combined absolute visual magnitude: +7.17
Combined visual luminosity: 0.12 x Sol
Observed Separation: 27.8 A.U.s
Year of separation observation: 1959
As seen from A:
     B would appear as magnitude -13.60
As seen from B:
     A would appear as magnitude -17.14


Component A:
Spectral class: K7e
Luminosity Class: V
Apparent visual magnitude: +8.86
Absolute visual magnitude: +7.21
Visual luminosity: 0.11 x Sol
Diameter: 0.74 x Sol
Source for diameter: Apparent Diameters and Absolute Radii of Stars (Fracassini+ 1988)
Comfort Zone (visual): 0.34 A.U.s
Angular size of star in sky in CZ: 1.168857 degrees


Component B:
Proper motion: 0.2 arcsec/yr (244.3° from north)
Radial Velocity: -2.5 km/sec
Source for proper motion and radial velocity: Gliese
Galactic (U,V,W) velocity components in km/s: 19.8, -2.19, 4.61
Spectral class: M
Luminosity Class: V
Apparent visual magnitude: +12.40
Absolute visual magnitude: +10.75
Visual luminosity: 0.0044 x Sol
Diameter: 0.42 x Sol
Source for diameter: Apparent Diameters and Absolute Radii of Stars (Fracassini+ 1988)
Comfort Zone (visual): 0.066 A.U.s
Angular size of star in sky in CZ: 3.386988 degrees

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