Stubbs A recent convergence of observational results has led cosmologists to the surprising conclusion that not only is the Universe expanding, but that the rate of expansion is increasing. This can be thought of as anti-gravity between regions of the vacuum. It appears that the Universe at present is dominated by the gravitational effect of this mysterious Dark Energy. Distant supernovae (exploding stars) provide a means to map out the history of the expansion of the Universe, and can be used to distinguish between different scenarios for the physics that drives an accelerating expansion. This project will detect and monitor over 200 supernovae in order to test different hypotheses for the nature of the Dark Energy.