| Radiation of CH4 and CO2 molecules with sunlight leads to the formation of complex organic molecules, including organic acids and other oxygenated hydrocarbons. Ultimately, these molecules condense into aerosol particles, and may have led to the formation of a global haze layer on the early Earth. Image is an illustrative composite prepared by Melissa G. Trainer using images of Titan and Earth. Image credit: NASA/JPL-Caltech |
