We use PHOENIX to model the atmospheres and spectra of substellar objects. This includes atmospheres of

  • Brown Dwarfs
  • Extrasolar Planets (also known as Exoplanets)

and as special but important cases of the above

  • Irradiated Planets and Brown Dwarfs

From a modeling point of view there is no difference between the two. In fact, there is not much difference to modeling cool stars. Atmospheres of substellar objects are dominated by molecules and condensates. The only difference between classical cool stars and substellar objects is the amount of condensates present in the atmosphere (and their effects on the atmosphere and spectrum). Condensates become important below effective temperatures of about 2500K.