Upsilon Andromedae

Proper names: Upsilon Andromedae, 50 Andromedae
Catalog numbers:
Gliese (Gl) 61, Henry Draper (HD) 9826, Bonner Durchmusterung (BD) +40°332 , Hipparcos Input Catalog (HIC) 7513, Smithsonian Astrophysical Observatory (SAO) 37362, Fifth Fundamental Catalogue (FK5) 1045, Hoffleit Bright Star (HR) 458
Age: 5900 million years
Source for age: Don C. Barry, "Chromospheric Age Dependence of…", APJ 334
Heavy element abundance: 70% of Sol
Standard error in heavy element abundance: 8%
Source for heavy element abundance: Strobel [Fe/H] Determinations
Arity: binary
Points of interest:
B. Edvardsson et al. measured a metallicity of about 110% of Sol for this star, from an iron-to-hydrogen ratio of over 120% the Solar value. They also deduced an age of only 2900 million years, but indicated that this age may have been underestimated by as much as 1200 million years.

Right Ascension and Declination: 1h36m47.842s, +41°24'19.64" (epoch 2000.0)
Distance from Sol: 43.93 light-years (13.47 parsecs)
Standard error in distance: 0.9604%
Source for distance: Hipparcos
Celestial (X,Y,Z) coordinates in ly: 30.05, 13.51, 29.05
Galactic (X,Y,Z) coordinates in ly: -27.85, 30.35, -15.25
Proper motion: 0.415 arcsec/yr (204.4° from north)
Radial Velocity: -28.7 km/sec
Source for proper motion and radial velocity: Gliese
Galactic (U,V,W) velocity components in km/s: 28.67, -22.37, -14.24

What do all these fields mean?

Data for A and B's orbit around one other:
Period: 20000 years
Observed Separation: 750 A.U.s
Source for orbit data: Lowrance et al.
As seen from B:
A would appear as magnitude -13.75

Component A:
Spectral class: F8
Luminosity Class: V
Apparent visual magnitude: +4.09
Absolute visual magnitude: +3.44
Visual luminosity: 3.650 x Sol
Color indices: B-V= +0.54
Mass: 1.2 x Sol
Source for mass: Lowrance
Diameter: 1.737 x Sol
Source for diameter: Apparent Diameters and Absolute Radii of Stars (Fracassini+ 1988)
Comfort Zone (visual): 1.910 A.U.s
Orbital period in CZ: 2.41038 years
Tidal index in CZ: 0.172119
Angular size of star in sky in CZ: 0.484719 degrees
Detected companions: 3
Companion b:
     Mass: 0.71 x Jupiter, minimum
     Source for mass: Marcy & Butler
     Period: 4.61700 days
     Standard Error in period: 0.0065%
     Semimajor Axis: 0.059 A.U.s
     Eccentricity: 0.034
     Periastron distance: 0.056994 A.U.s
     Apastron distance: 0.061006 A.U.s
     Source for orbit data: Marcy & Butler
Companion c:
     Mass: 2.11 x Jupiter, minimum
     Source for mass: Marcy & Butler
     Period: 241.2 days
     Standard Error in period: 0.46%
     Semimajor Axis: 0.83 A.U.s
     Eccentricity: 0.18
     Periastron distance: 0.6806 A.U.s
     Apastron distance: 0.9794 A.U.s
     Source for orbit data: Marcy & Butler
Companion d:
     Mass: 4.61 x Jupiter, minimum
     Source for mass: Marcy & Butler
     Period: 3.47 years
     Standard Error in period: 2.4%
     Semimajor Axis: 2.5 A.U.s
     Eccentricity: 0.41
     Periastron distance: 1.475 A.U.s
     Apastron distance: 3.525 A.U.s
     Source for orbit data: Marcy & Butler

Component B:
Spectral class: M4.5
Luminosity Class: V
Mass: 0.2 x Sol
Source for mass: Lowrance

Data for this star system were most recently updated on 30-September-2003.