Recent advances in astronomical instrumentation have permitted small observatories in liberal arts colleges to automate the operation of their telescopes and to measure the brightnesses of astronomical objects quickly and accurately with modern "CCD" (Charged Couple Device) detectors. In the last few years the Principal Investigator (PI) and his colleagues have used awards from the Keck Foundation and the NSF to upgrade their Wesleyan University 24-inch telescope in these ways. In this NSF grant he plans to use them as a combined research and teaching tool for undergraduates. The PI and his students will observe selected T Tauri and supernova stars over time. The T Tauri stars are thought to be extremely young, and are known to have both irregular and periodic components to their variability. The irregular component is likely to arise from material falling onto a circumstellar disk around the star. In contrast, the periodic component is likely to be produced by the appearance and subsequent disappearance of a magnetic "spot" from our view as the star rotates. A secondary project will be the monitoring of supernovae light in nearby galaxies. Supernovae are known to be members of a discrete number of subgroups each with well defined properties determined by their "light curve" with time. These properties can be related to the absolute luminosity of the supernova. The PI will monitor supernova light curves in order to determine how many belong to each of these subgroups, thereby providing information on the probability of different types of supernova-generating evolutionary scenarios, as well as the absolute luminosities of these stars themselves. By comparing observed brightnesses with derived luminosities the PI will be able to determine the distance to the supernova and hence the external galaxy.
