  We present a statistical technique which can be used to detect the presence
and properties of moving sources contributing to a diffuse background. The
method is a generalization of the 2-point correlation function to include
temporal as well as spatial information. We develop a formalism which allows
for a derivation of the spacetime 2-point function in terms of the properties
of the contributing sources. We test this technique in simulated sky maps, and
demonstrate its robustness in identifying the presence of moving and stationary
sources. Applications of this formalism to the diffuse gamma-ray background
include searches for solar system bodies, fast moving primordial black holes,
and dense cores of dark matter proto-halos in the solar neighborhood. Other
applications include detecting the contribution of energetic neutrinos
originating in the solar system, as well as probing compact objects in long
timeline lensing experiments.
