  The rise in the energy spectrum of the positron ratio, observed by the PAMELA
satellite above 10 GeV, and other cosmic ray measurements, have been
interpreted as a possible signature of Dark Matter annihilation in the Galaxy.
However, the large number of free parameters, and the large astrophysical
uncertainties, make it difficult to do conclusive statements about the
viability of this scenario. Here, we perform a multi-wavelength,
multi-messenger analysis, that combines in a consistent way the constraints
arising from different astrophysical observations. We show that if standard
assumptions are made for the distribution of Dark Matter (we build models on
the recent Via Lactea II and Aquarius simulations) and the propagation of
cosmic rays, current DM models cannot explain the observed positron flux
without exceeding the observed fluxes of antiprotons or gamma-ray and radio
photons. To visualize the multi-messenger constraints, we introduce "star
plots", a graphical method that allows to show in the same plot theoretical
predictions and observational constraints for different messengers and
wavelengths.
