Atmosphere of Pluto by the spacecraft "New Horizons". The main component of the atmosphere of Pluto is nitrogen. Content of methane, according to measurements by "New Horizons", is 0.25%. For carbon monoxide, the Earth-based estimates are (2010) and (2015). Under influence of high-energy cosmic radiation, these gases react to form more complex compounds (not volatile at Pluto's surface temperatures), including ethane (CH), ethylene (CH), acetylene (CH), heavier hydrocarbons and nitriles and hydrogen cyanide (HCN) (amount of ethylene is about 0.0001%, and amount of acetylene is about 0.0003%). These compounds slowly precipitate on the surface. Probably, they also include tholins, which are responsible for
Earth analog or coal), interaction with the atmosphere, volcanically or artificially. A true Earth analog therefore might need to have formed through similar processes, having possessed an atmosphere, volcanic interactions with the surface, past or present liquid water and life forms. There are several factors that can determine planetary temperatures and therefore several measures that can draw comparisons to that of the Earth in planets where atmospheric conditions are unknown. Equilibrium temperature is used for planets without atmospheres. With atmosphere, a greenhouse effect is assumed. Finally, surface temperature is used. Each of these temperatures is affected by climate, which is influenced by