While the latter anisotropy may be somewhat difficult to detect, this feature in the solar component discussed here would be more pronounced due to the proximity of the Sun and the underlying production mechanism. This provides additional motivation for studies of the positional, directional, and temporal features of the existing PAMELA and Fermi data sets.

In order to go further and actually attempt to fit the PAMELA and Fermi data, a better understanding of the predicted energy spectrum would be required, which goes beyond the scope of this paper. Of course, this is also quite model dependent. For example, a simple underlying two-body decay of the mediator to $e^+e^-$ pairs will result in a very hard spectrum, which may not fit the observed spectrum. However, the spectrum can be softened through cascade decays, or the re-scattering of mediators inside the solar interior. It would also be important to understand to what extent the electron/positron energy spectrum is affected or softened by interaction with the solar atmosphere and through propagation from the sun to the earth.

### 2.3 Other local sources {#other-local-sources .unnumbered}

The Sun represents by far the largest astronomical body in the solar system, and presumably the most efficient 