Epsilon Indi

Proper names: Epsilon Indi
Catalog numbers:
     Gliese (Gl) 845, Henry Draper (HD) 209100, Cape Photographic Durchmusterung (CPD) -57°10015, Luyten Half-Second (LHS) 67, Hipparcos Input Catalog (HIC) 108870, Smithsonian Astrophysical Observatory (SAO) 247287, UGPMF 544, Fifth Fundamental Catalogue (FK5) 825, Hoffleit Bright Star (HR) 8387
Heavy element abundance: 84% of Sol
Standard error in heavy element abundance: 30%
Source for heavy element abundance: Strobel [Fe/H] Determinations
Arity: singular
Points of interest:
     The two brown dwarf companions to this star both belong to spectral class T. The pair orbit each other at least two A.U.s apart, and have an observed separation from Epsilon Indi A of about 7 arcminutes (putting the pair at least 1500 A.U.s away from the star.)
    Epsilon Indi Ba has a surface temperature of roughly 1500° Celsius, and an intrinsic luminosity just 0.002% that of the Sun.

Right Ascension and Declination: 22h3m21.643s, -56°47'9.58" (epoch 2000.0)
Distance from Sol: 11.83 light-years (3.626 parsecs)
Standard error in distance: 0.2496%
Source for distance: Hipparcos
Celestial (X,Y,Z) coordinates in ly: 5.658, -3.157, -9.896
Galactic (X,Y,Z) coordinates in ly: 7.159, -3.158, -8.868
Proper motion: 4.7 arcsec/yr (122.9° from north)
Radial Velocity: -40.4 km/sec
Source for proper motion and radial velocity: Gliese
Galactic (U,V,W) velocity components in km/s: -80.21, -41.36, 3.836

What do all these fields mean?

Data for A and (Ba-Bb)'s orbit around one other:
Combined absolute visual magnitude: +6.89
Combined visual luminosity: 0.153 x Sol
Observed Separation: 1523 A.U.s
As seen from (Ba-Bb):
     A would appear as magnitude -8.77

Spectral class: K5e
Luminosity Class: V
Apparent visual magnitude: +4.69
Absolute visual magnitude: +6.89
Visual luminosity: 0.153 x Sol
Color indices: B-V= +1.06, U-B= +0.99, R-I= +0.40
Mass: 0.59 x Sol
Diameter: 1.387 x Sol
Source for diameter: Apparent Diameters and Absolute Radii of Stars (Fracassini+ 1988)
Comfort Zone (visual): 0.391 A.U.s
Orbital period in CZ: 116.128 days
Tidal index in CZ: 9.89245
Angular size of star in sky in CZ: 1.893185 degrees
Detected companions: 2
Companion Ba:
     Mass: 32 x Jupiter
     Source for mass: Smith et al. (2003)
     Observed Separation: 2.2 A.U.s
     Source for orbit data: Walker and Howat / Volk and Blum
Companion Bb:
     Observed Separation: 2.2 A.U.s
     Source for orbit data: Walker and Howat / Volk and Blum

Data for this star system were most recently updated on 21-September-2003.