Atmosphere of Triton produced by the photolysis of methane. This hydrogen quickly escapes into the space serving as a source of plasma in the magnetosphere of Neptune. Other Solar System planets, dwarf planets, and moons with atmospheres of similar composition include Earth, Titan, Pluto and, possibly, . Triton's atmosphere is well structured and global. The atmosphere extends up to 800 kilometers above the surface, where the exobase is located, and had a surface pressure of about 14 microbars as of 1989. This is only 1/70,000th of the surface pressure on Earth. The surface temperature was at least because Triton's nitrogen ice is in
Atmosphere of Earth temperature record of Earth – with the exception of one cold glacial phase about 2.4 billion years ago. In the late Archean Eon an oxygen-containing atmosphere began to develop, apparently produced by photosynthesizing cyanobacteria (see Great Oxygenation Event), which have been found as stromatolite fossils from 2.7 billion years ago. The early basic carbon isotopy (isotope ratio proportions) strongly suggests conditions similar to the current, and that the fundamental features of the carbon cycle became established as early as 4 billion years ago. Ancient sediments in the Gabon dating from between about 2,150 and 2,080 million years ago provide a