Gliese 781.1

light-years

Catalog numbers:
     Gliese (Gl) 781.1, Hipparcos Input Catalog (HIC) 99150
Arity: binary
Right Ascension and Declination: 20h7m44.99s, -31°45'13.6" (epoch 2000.0)
Distance from Sol: 47.6 light-years (14.6 parsecs)
Standard error in distance: 7.0187%
Source for distance: Hipparcos
Celestial (X,Y,Z) coordinates in ly: 21.4, -34.4, -25.1
Galactic (X,Y,Z) coordinates in ly: 40.7, 7.37, -23.6
Proper motion: 0.796 arcsec/yr (158.8° from north)
Source for proper motion: Gliese

What do all these fields mean?

Data for A and B's orbit around one other:
Combined absolute visual magnitude: +10.79
Combined visual luminosity: 0.0042 x Sol
Observed Separation: 599 A.U.s
As seen from A:
     B would appear as magnitude -6.01
As seen from B:
     A would appear as magnitude -6.26


Component A:
Catalog numbers:
     Luyten Half-Second (LHS) 3524, Luyten Palomar (LP) 926-52, Luyten (L) 565-62
Spectral class: M3
Luminosity Class: V-VI
Apparent visual magnitude: +12.25
Absolute visual magnitude: +11.43
Visual luminosity: 0.0023 x Sol
Color indices: B-V= +1.55, U-B= +1.11, R-I= +1.06
Comfort Zone (visual): 0.048 A.U.s


Component B:
Catalog numbers:
     Luyten Half-Second (LHS) 3523, Luyten Palomar (LP) 926-51, Luyten (L) 565-63
Right Ascension and Declination: 20h4m35s, -31°53'18" (epoch 1950.0)
Celestial (X,Y,Z) coordinates in ly: 20.9, -34.6, -25.2
Galactic (X,Y,Z) coordinates in ly: 41.0, 7.16, -23.2
Spectral class: M3.5
Luminosity Class: V-VI
Apparent visual magnitude: +12.50
Absolute visual magnitude: +11.68
Visual luminosity: 0.0019 x Sol
Color indices: B-V= +1.63, U-B= +1.07, R-I= +1.18
Comfort Zone (visual): 0.043 A.U.s

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