Local gamma-ray sources

The quiet Sun, the Moon, the Earth and other Solar System objects are sources of high-energy gamma rays. The emission is produced by interactions of Galactic cosmic rays: by nucleons in the surface and atmosphere of the sources via hadronic interactions, and by electrons on solar photons in the heliosphere via inverse Compton scattering. Both emissions depend on the solar activity and hence on the modulation of cosmic rays in the heliosphere. At the minimum of the solar activity, Galactic cosmic rays have their maximum flux, and hence the brightest gamma-ray emission is expected. For this reason, solar and lunar emission provides a unique probe of cosmic-ray propagation in the inner heliosphere. Here I give a review of the gamma-ray emission mechanisms from the local sources, and present the status of the observations