NOTE: This animation attempts to relate the possible
orbits of 94 Ceti AB (and their current, if brief, habitable
zone) to their common center of mass. Although the initial
display shows the system's actual orbital tilt (at an
inclination of 66°) from the visual perspective of an observer
on Earth, the orbital inclination of the known planetary companion
"b" around Star A may be be different from that of the habitable
zone orbit depicted here.

According to the new
Sixth
Catalog of Orbits of Visual Binaries, Stars A and B
have an average separation of 151 AUs (6.77" at a HIPPARCOS
distance estimate of 73.0 light-years -- 3.3" at 231°
in 1958). Inclined at 114.10° (Sixth Catalog) or 66°
(original source) to Earth's line of sight, their eccentric
orbit (e= 0.26) takes about 1,470 years to complete
(Alan
Hale, 1994, pages 312 and 314).

On August 7, 2000, a team of astronomers
(Dominique Naef,
Francisco Pepe,
Michel
Mayor,
Nuno C. Santos,
Didier Queloz,
Stephane Udry, and M. Burnet) announced the discovery of a
Jupiter-like planet around this Sun-like star
(Observatoire
de Genève and
exoplanets.org).
Planet "b" has at least 1.66 times of Jupiter's mass.
It moves around Star A at an average distance of 1.19 AUs (a
semi-major axis between the orbital distances of Earth and Mars)
in an elliptical orbit (e=0.20) that takes 454 days or
over 1.2 years to complete.

The orbit of an Earth-like planet (with liquid water) around
Star A may be centered around 2.11 AUs -- within the inner
reaches of the Main Asteroid Belt in the Solar System --
with an orbital period of 2.69 years. However, the presence of
planet b in an eccentric orbit with an average distance of 1.19
AUs would probably disrupt the orbital stability of an
Earth-type planet in Star A's water zone. Astronomers would find it
very difficult to detect an Earth-type planet in the water zone
of this star using present methods.

The orbit of an Earth-like planet (with liquid water) around
Star B may be centered around 0.102 AUs -- well within the
orbital distance of Mercury in the Solar System --
with an orbital period of 16.5 days. Hence, such a planet is
likely to be tidally locked with Star B with perpetual
daylight on one side.