Presentation 1 : None
VLT spectroscopic observations of HD209458b during transit: search for signatures of a planetary exosphere
Moutou, Coustenis, Iro, Mayor, Queloz
HD209458 is the first known star where a hot Jupiter-like planet was
fully characterized, with the aid of both RV and transit detection methods.
Ground-based follow-up observations of this system have been carried
out on the VLT instruments UVES and ISAAC. We searched for absorption
features of the planetary extended atmosphere on top of the star spectrum
by comparing the spectra obtained at different epochs, during the
planetary transit and out of transit. Careful data reduction is required
to achieve the highest accuracy since the expected signatures could be
extremely faint. A description of the present state of our data set will
be given together with perspectives towards future searches in this area.