We seek construction funds for PanSTARRS-2, a unique pair of wide-field optical survey telescopes to be
built on Mount Haleakala in Hawaii. PanSTARRS-2 will be the most powerful wide-field imaging facility in existence and, by providing coverage of the northern stars, will give Australian astronomers the all-sky coverage needed to solve several fundamental problems in astrophysics and cosmology. Our marquee experiment will be to use observations of galaxies from PanSTARRS-2 to produce the largest map of Dark Matter ever made and to constrain the nature of Dark Energy. Other experiments will allow us to understand the formation of the first stars, the physics of cosmic explosions, and the assembly and evolution of galaxies.