Triatomic oxygen, also known as ozone, is a molecule composed of three oxygen atoms. It is a pale blue gas with a pungent odor and is found in small amounts in the Earth's atmosphere. Ozone is formed by the action of ultraviolet radiation on oxygen molecules, and it plays a crucial role in protecting life on Earth by absorbing harmful ultraviolet radiation from the sun. In the stratosphere, ozone forms a layer that shields the Earth from most of the sun's UV radiation, making it possible for life to thrive on the planet's surface. Ozone also plays a role in the chemistry of the troposphere, where it can act as both an oxidizing agent and a free radical, participating in various chemical reactions that affect air quality and climate.