Wednesday 13 May 2015: Seminar: Getting to know HD209458b: the challenges of interpreting exoplanet data"
Dr Tom Evans - University of Exeter
Physics, 4th floor 14:00-15:00
The hot Jupiter HD209458b was the first exoplanet observed to transit its host star, and has been studied intensely ever since. I will focus on infrared observations made with the Spitzer/IRAC instrument, which have been influential in shaping our understanding of HD209's atmospheric structure and composition. These IRAC datasets are affected by instrumental systematics that overwhelm the faint atmosphere signal from the planet, making analysis of these data challenging. I will describe the application of Gaussian process models to this problem, which is a relatively new approach in the exoplanet field. The results produced by this analysis call into question a number of previous claims about HD209's atmosphere, and add to a growing body of evidence suggesting clouds play an important role in many hot Jupiters' atmospheres.