Starspots are not well understood for contact binary star systems. The following properties of spots were systematically investigated: temperature, radius, colatitude, and longitude. Spots were modeled on an AE Phe like contact binary system. The spots were changed in a systematic manner. The light curve phases of primary minimum and primary maximum were affected by these parameter changes in a systematic manner, as well as the secondary minimum and maximum. It will be shown that it is possible to use the shift in these phases to study starspots over time. This information can also be used to identify the presence of spots in binary star systems.Starspots on contact binary systems are not commonly found at a longitude near 180°. The results of this study show that starspots near 180° should be the easiest to detect using photometric techniques. This is the most significant result from this study. Either there is an unknown physical reason why contact binary stars do not have starspots near a longitude of 180°, or the starspots are there and the photometric data has been misinterpreted. / Department of Physics and Astronomy

In this investigation of near-contact binary stars, the author fit a synthetic light, computer generated, curve model to observations by adjusting various parameters of two near-contact binary pairs, CN Andromeda and TZ Draconis. By fitting asymmetries in the light curves using spotting parameters, the spotting activity for both stars can be determined. From the spotting parameters it is possible to compare the spotting activity of these two near-contact binaries to the spotting activity of 47 contact binaries (Csizmadia et al., 2004). The author determined that, for both TZ Dra and CN And, spots are located at positions that were previously not seen in other observations of contact binaries (Hill, 2007). / Department of Physics and Astronomy