DescriptionStarspots are dark regions on a star's surface that trace areas of strong magnetic fields. On the Sun, spots are typically small and occur in bands near the stellar equator. Sunspot occurrence frequency also peaks every 11 years due to the "solar cycle". For younger stars there are indications that spots are larger, and can form near the stellar poles, while evidence for spot activity cycles on other stars is sparse. These differences indicate that the shape and strength of the internal magnetic dynamo evolves throughout a stars life. However, because of their great distance we cannot directly observe the surface of other stars to map the locations and sizes of spots. We have developed new software to model the signature of starspots in Kepler data from transiting exoplanet systems. These star-planet systems are unique in having an orbiting planet that passes directly in front of its parent star. When the planet transits the star, it will briefly pass over spots on the star's surface, giving a very small change in the apparent brightness of the system. To trace the evolution of spot size and location with stellar age we must extend our analysis to many star systems with different transiting planet orientations. A startup allocation from XSEDE will allow us to test our software's ability to map spots from different system orientations, and using many years worth of Kepler data.
OrganizationWestern Washington University
Sponsor Campus GridOSG-XSEDE
Principal Investigator
James Davenport
Field Of ScienceAstrophysics