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
The Songs of Distant Earth would have to carry to first accelerate to the speeds required to travel such great distances within an acceptable time, and then decelerate upon approaching the destination. This limitation is overcome however with the development of the Quantum Drive less than a hundred years before the Sun is set to become a nova. This scientific break-through allows the construction of a fleet of manned interstellar vehicles, including the Starship "Magellan". The "Magellan" escapes the Earth three years before the Sun explodes, an event that is witnessed by the "Magellan"'s crew. In the intervening years the colony on Thalassa loses contact