 Current unsolved problems for the field of astroparticle physics include characterization of dark matter and dark energy.Observations of the orbital velocities of stars in the Milky Way and other galaxies starting with Walter Baade and Fritz Zwicky in the 1930s, along with observed velocities of galaxies in galactic clusters, found motion far exceeding the energy density of the visible matter needed to account for their dynamics.Since the early nineties some candidates have been found to partially explain some of the missing dark matter, but they are nowhere near sufficient to offer a full explanation.