  In this paper, we study the stochastic heat equation in the spatial domain
$\mathbb{R}^d$ subject to a Gaussian noise which is white in time and colored
in space. The spatial correlation can be any symmetric, nonnegative and
nonnegative-definite function that satisfies {\it Dalang's condition}. We
establish the existence and uniqueness of a random field solution starting from
measure-valued initial data. We find the upper and lower bounds for the second
moment. As a first application of these moments bounds, we find the necessary
and sufficient conditions for the solution to have phase transition for the
second moment Lyapunov exponents. As another application, we prove a
localization result for the intermittency fronts.
