Titan orbits Saturn once every 15 days and 22 hours. Like
the Moon, and many of the satellites of the gas giants, its rotational period
is identical to its orbital period; Titan is thus tidally locked in synchronous
rotation with Saturn, and always shows one face to the planet. Because of this,
there is a sub-Saturnian point on its surface, from which the planet would
appear to hang directly overhead. Longitudes on Titan are measured westward
from the meridian passing through this point. Its orbital eccentricity is
0.0288, and the orbital plane is inclined 0.348 degrees relative to the
Saturnian equator.
Viewed from Earth, Titan reaches an angular distance of
about 20 Saturn radii (just over 1,200,000 kilometres (750,000 mi)) from Saturn
and subtends a disk 0.8 arcseconds in diameter.
The small, irregularly shaped satellite Hyperion is locked
in a 3:4 orbital resonance with Titan. A "slow and smooth" evolution
of the resonance—in which Hyperion would have migrated from a chaotic orbit—is
considered unlikely, based on models. Hyperion probably formed in a stable
orbital island, whereas the massive Titan absorbed or ejected bodies that made
close approaches.
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