New Transit Measurements of WASP 43b and HD 189733b

Known exoplanets not only provide excellent targets for students who are learning to acquire data with remote observatories and to process the data but also fulfill a scientific need for repeated measurements to determine the stability of known parameters. We present recent measurements taken by undergraduate students with a remotely accessed telescope at the Dark Skies Observatory Collaborative in West Texas on two well-studied exoplanets. WASP 43b has a published orbital period of 0.81347753 days and its host K7V star has a visual magnitude of 12.4. HD 189733b has a published orbital period of 2.21857312 days around its K1V star of visual magnitude 7.67. Both planets orbit within the corona of their host stars and, as such, appear to experience changes in their orbital periods, transit timings, and other parameters. We examined the historical trends, combined them with our measurements in the mid-transit timings for the stars, and determined there are significant changes. Astronomers– from college students to professionals–need this continued monitoring in order to keep system models up to date.