  As hints of physics beyond the standard model become the major driving force
behind future large-scale projects, it is increasingly important to consider
all sources of evidence and constraints. Here, I illustrate the importance of
considering the connection between particle physics, cosmology and
astrophysics, mainly via two examples: 1) the sterile neutrino and its impact
on cosmology, and 2) the 511 keV line from electron-positron annihilation in
the galactic centre.
