Orbital Distance (a=AUs)	Orbital Period (P=years)	Orbital Eccentricity (e)	Orbital Inclination (i=degrees)	Mass Estimate (Solar)	Diameter (Solar)	Density (Earths)	Surface Gravity (Earths)	Metallicity (Solar)
Bab Mass Center	0.000	...	...	...	...	...	...	...	...
Castor Ba	0.0057	0.00802	0.01	?	1.7?	1.6	...	...	<1
Castor Bb	0.024	0.00802	0.01	?	0.4?	<1	...	...	<1
H.Z. Bab	~4	5.5	0	?	...	...	...	...	...

NOTE: This animation attempts to relate the orbits and possible habitable zone of stars Ba and Bb in the Castor system to their center of mass. For the purposes of this animation, the masses of stars Ba, and Bb are assumed to be 1.7 and 0.4 Solar, respectively. You will need to vastly expand the field of view to see the orbital motion of the two stars around their center of mass.

Stars Ba and Bb have a combined visual luminosity of more than 14 times that of Sol's. They are separated on average by only 0.03 AUs (of a semi-major axis). Their highly circular orbit (e= 0.01) takes only 2.93 days to complete (Joel Stebbins, 1914, pp. 465-466; and Heber D. Curtis, 1906), and suggests synchronous rotation (Schmitt et al, 1994, page 850). Currently, the circumbinary orbit of an Earth-like planet (with liquid water) around Stars Aab may be centered around 4 AU -- on the outer edge of the Main Asteroid Belt in the Solar System.