Ozone–oxygen cycle Ozone–oxygen cycle The ozone–oxygen cycle is the process by which ozone is continually regenerated in Earth's stratosphere, converting ultraviolet radiation (UV) into heat. In 1930 Sydney Chapman resolved the chemistry involved. The process is commonly called the Chapman cycle by atmospheric scientists. Most of the ozone production occurs in the tropical upper stratosphere and mesosphere. The total mass of ozone produced per day over the globe is about 400 million metric tons. The global mass of ozone is relatively constant at about 3 billion metric tons, meaning the Sun produces about 12% of the ozone layer each day. And if
Upper Atmosphere Research Satellite Upper Atmosphere Research Satellite The Upper Atmosphere Research Satellite (UARS) was a NASA-operated orbital observatory whose mission was to study the Earth’s atmosphere, particularly the protective ozone layer. The satellite was deployed from Space Shuttle "Discovery" during the STS-48 mission on 15 September 1991. It entered Earth orbit at an operational altitude of , with an orbital inclination of 57 degrees. The original mission duration was to be only three years, but was extended several times. When the mission finally ended in June 2005 due to funding cuts, 14 years after the satellite's launch, six of its ten instruments were