Extraterrestrial atmosphere star undergoing runaway greenhouse effect. For planets in the habitable zone, it was thought that water photolysis would be strongly limited by cold-trapping of water vapour in the lower atmosphere. However, the extent of HO cold-trapping depends strongly on the amount of non-condensible gases in the atmosphere such as nitrogen N and argon. In the absence of such gases, the likelihood of build-up of oxygen also depends in complex ways on the planet's accretion history, internal chemistry, atmospheric dynamics, and orbital state. Therefore, oxygen, on its own, cannot be considered a robust biosignature. The ratio of nitrogen and argon to
Greenhouse Gases Observing Satellite band to enhance observation accuracy. The satellite uses a spectrometer to measure different elements and compounds based on their response to certain types of light. This technology allows the satellite to measure "the concentration of greenhouse gases in the atmosphere at a super-high resolution." Greenhouse Gases Observing Satellite The Greenhouse Gases Observing Satellite (GOSat), also known as , is an Earth observation satellite and the world's first satellite dedicated to greenhouse-gas-monitoring. It measures the densities of carbon dioxide and methane from 56,000 locations on the Earth's atmosphere. The GOSAT was developed by the Japan Aerospace Exploration Agency (JAXA) and launched