Knowledge Bank

Observations of methane absorption bands in the spectra of the atmospheres of some of the outer planets suggests the possibility of methane in condensed phases being present in clouds in planetary atmospheres. The scattering and absorption of solar infrared radiation by atmospheric cloud particles can be calculated from Mic theory provided that values of the optical constants $N^=n+ik$ are known. The Infrared optical constants of liquid methane have been determined from Kramers-Kronig analysis of near-normal incidence reflectance measurements. The results obtained will be presented and compared with results from previous transmission studies of solid methane.