  All stars exhibit universal central behavior in terms of new homology
variables (u,w). In terms of these variables, we obtain simple analytic fits to
numerical standard solar models for the core and radiative zones of the ZAMS
and present Suns, with a few global parameters. With these analytic fits,
different theoretical models of the solar core, neutrino fluxes, and
helioseismic observations can be parametrized and compared.
