The role of hydrocarbons in the lonospheres of the outer planets

Abstract

The role of hydrocarbons as a possible sink for H+ and H3+ ions in the lower ionosphere of the outer planets is examined. Calculations indicate that H+ and H3+ are efficiently converted to hydrocarbon ions on reaction with methane. The terminal ions, CH5+ and C2H5+ are rapidly neutralized in dissociative recombination with electrons. Extreme ultraviolet photolysis of hydrocarbons as a potential additional source of lower elevation ions in investigated.