|AB Mass Center||0.0||...||...||...||...||...||...||...||...|
|Chi Draconis A||0.42||0.768||0.414||74.8||1.03||1.2||...||...||0.47|
|Chi Draconis B||0.57||0.768||0.414||74.8||0.75||...||...||...||0.47|
|Disrupted H.Z. AB||1.45||1.31||0||74.8||...||...||...||...||...|
NOTE: This animation attempts to relate the orbits (and possible habitable zones) of Stars A and B in the Chi Draconis AB system to their common center of mass. To enlarge the display, the orbits have been arbitrarily rotated 45 degrees. Although the initial display shows the system's actual orbital tilt (at an inclination of 74.8°) from the visual perspective of an observer on Earth, the orbital inclination of any planet that may be discovered someday around either star would likely be different from those of the habitable zone orbits depicted here.
Previous orbital calculations (Tomkin et al, 1987; and Duquennoy and Mayor, 1991, page 9 and 22) have been slightly revised. According to new measurements (Dimitri Pourbaix, 2000) found in the new Sixth Catalog of Visual Orbits of Binary Stars, Stars A and B have an "average" separation (semi-major axis) of 0.991 AU, that varies between 0.6 and 1.4 AUs in an eccentric orbit (e= 0.414) that takes 280.5 days -- over three-quarters of an Earth year -- to complete. The inclination of their orbit is 74.8° from the perspective of an observer on Earth. Despite the closeness of the binary orbit, there appears to be significant noncoplanarity between the orbital and equatorial planes of Star A (Alan Hale, 1994, pages 18-19). According to one estimate based on the combined luminosity of this relatively close binary, the distance from Chi Draconis AB where an Earth-type planet would be "comfortable" with liquid water may be centered around 1.45 AU -- just inside the orbital distance of Mars in the Solar System. Unfortunately, this is too close for a stable orbit around both two stars.
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