  We study the stabilities and classical solutions of Euler-Poisson equations
of describing the evolution of the gaseous star in astrophysics. In fact, we
extend the study the stabilities of Euler-Poisson equations with or without
frictional damping term to some special dimensional spaces. Besides, by using
the second inertia function in 2 dimension of Euler-Poisson equations, we prove
the non-global existence of classical solutions with $2\int_{\Omega}(\rho| u|
^{2}+2P)dx<gM^{2}-\epsilon$, for any $\gamma$.
