Detection of Heavy Element Chemistry in Exoplanetary Atmospheres
Transmission spectroscopy, which entails the detection of minute wavelength-dependent variations of the inferred planetary radius due to an optically thick atmosphere, provides us with a unique opportunity of detecting and characterising atmospheres of exoplanets. This is essential to understanding the formation of these alien worlds, the evolutionary paths that they embark on and most importantly provide a path to detection of biomarkers in possibly habitable exoplanets.
Ground-based observatories (VLT and Gemini for instance) have played a vital role, and will continue to do so, in complementing results from space-bound telescopes (HST, JWST). I will present my most recent result from ESO's FORS2 instrument at UT1 of the VLT, that being the first detection of a metal oxide in an atmosphere of an exoplanet. This result is particularly important in detection of biomarkers in exoplanetary atmospheres, as those species would have absorbing bands with similar characteristics to those of TiO detected in the atmosphere of WASP-19b (Sedaghati+ 2017b, Nature, 549, 238–241).