Department of Astronomy & Physics
Time: November 3, 2017 - 3:00 PM
Location: Atrium 101
While being a treasure of information for stellar physicists, stellar activity is a major source of headaches for exoplaneteers. Transit photometry and radial velocities, the main techniques to measure the radius and mass of exoplanets, are affected by the noise and systematic errors introduced by phenomena related to stellar activity, such as starspots. This is a serious limitation because the mass and radius of a planet are necessary parameters to model its internal structure. Starspots also affect the atmospheric characterization of exoplanets, as they can mimic particular spectral features which can erroneously be interpreted as aerosol signatures in otherwise clear atmospheres.
I will review the main challenges due to stellar activity and present different ways it can be dealt with, with their advantages and disadvantages, discussing real cases. We are far from the solution to this problem, but recent improvements in survey precision, analytic modeling and computational techniques give some reasons to be optimistic.