Alpha Caeli

Proper names: Alpha Caeli
Catalog numbers:
Gliese (Gl) 174.1, Henry Draper (HD) 29875, Cordoba Durchmusterung (CD) -42°1587, Hipparcos Input Catalog (HIC) 21770, Smithsonian Astrophysical Observatory (SAO) 216926, Fifth Fundamental Catalogue (FK5) 1129, Hoffleit Bright Star (HR) 1502, Woolley (Wo) 9164
Arity: binary
Right Ascension and Declination: 4h40m33.708s, -41°51'49.73" (epoch 2000.0)
Distance from Sol: 65.7 light-years (20.1 parsecs)
Standard error in distance: 1.0558%
Source for distance: Hipparcos
Celestial (X,Y,Z) coordinates in ly: 16.6, 46.0, -43.8
Galactic (X,Y,Z) coordinates in ly: -20.1, -45.2, -43.2
Proper motion: 0.166 arcsec/yr (242.7° from north)
Radial Velocity: 0.8 km/sec
Source for proper motion and radial velocity: Gliese
Galactic (U,V,W) velocity components in km/s: 9.75, 5.34, -11.3

What do all these fields mean?

Data for A and B's orbit around one other:
Combined absolute visual magnitude: +2.92
Combined visual luminosity: 5.92 x Sol
Observed Separation: 133 A.U.s
Year of separation observation: 1933
As seen from A:
B would appear as magnitude -9.97
As seen from B:
A would appear as magnitude -18.03

Component A:
Spectral class: F2
Luminosity Class: V
Apparent visual magnitude: +4.44
Absolute visual magnitude: +2.92
Visual luminosity: 5.91 x Sol
Color indices: B-V= +0.34, U-B= +0.01, R-I= +0.20
Diameter: 1.11 x Sol
Source for diameter: Apparent Diameters and Absolute Radii of Stars (Fracassini+ 1988)
Comfort Zone (visual): 2.43 A.U.s
Angular size of star in sky in CZ: 0.244293 degrees

Component B:
Spectral class: M
Luminosity Class: V
Apparent visual magnitude: +12.50
Absolute visual magnitude: +10.98
Visual luminosity: 0.0035 x Sol
Diameter: 0.45 x Sol
Source for diameter: Apparent Diameters and Absolute Radii of Stars (Fracassini+ 1988)
Comfort Zone (visual): 0.059 A.U.s
Angular size of star in sky in CZ: 4.038170 degrees

Data for this star system were most recently updated on 4-April-2001.