Models of Stars, Brown Dwarfs and Exoplanets

Within the next few years, GAIA and several instruments aiming at imag- ing extrasolar planets will see first light. In parallel, low mass planets are being searched around red dwarfs which offer more favourable conditions, both for radial velocity de- tection and transit studies, than solar-type stars. Authors of the model atmosphere code which has allowed the detection of water vapour in the atmosphere of Hot Jupiters re- view recent advancement in modelling the stellar to substellar transition. The revised solar oxygen abundances and cloud model allow for the first time to reproduce the pho- tometric and spectroscopic properties of this transition. Also presented are highlight results of a model atmosphere grid for stars, brown dwarfs and extrasolar planets.