  We fit an isothermal oscillatory density model of Saturn's protoplanetary
disk to the present-day major satellites and innermost rings D/C and we
determine the radial scale length of the disk, the equation of state and the
central density of the primordial gas, and the rotational state of the
Saturnian nebula. This disk does not look like the Jovian and Uranian disks
that we modeled previously. Its power-law index is extremely steep ($k=-4.5$)
and its radial extent is very narrow ($\Delta R\lesssim 0.9$ Gm), its rotation
parameter that measures centrifugal support against self-gravity is somewhat
larger ($\beta_0=0.0431$), as is its radial scale length (395 km); but, as was
expected, the size of the Saturnian disk, $R_{\rm max}=3.6$ Gm, takes just an
intermediate value. On the other hand, the central density of the compact
Saturnian core and its angular velocity are both comparable to that of
Jupiter's core (density of $\approx 0.3$~g~cm$^{-3}$ in both cases, and
rotation period of 5.0 d versus 6.8 d); and significantly less than the
corresponding parameters of Uranus' core. As with the other primordial nebulae,
this rotation is sufficiently slow to guarantee the disk's long-term stability
against self-gravity induced instabilities for millions of years of evolution.
