Nitrogen Cycle: The biogeochemical cycle that describes the transformation and movement of nitrogen through the environment, involving processes such as nitrogen fixation, nitrification, and denitrification.
Methane:A hydrocarbon gas with the chemical formula CH4, which is the simplest alkane and is a major component of the atmospheres of the giant planets.
Spectroscopy:The study of the interaction between matter and electromagnetic radiation, used to analyze the composition and properties of stars and other celestial bodies.