The right answer is to shield the earth from harmful solar radiation
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At room temperature, ozone - of formula O3 and sometimes called trioxygen - is a gas whose molecules make up three atoms of oxygen. It is almost colorless - although it may be perceived by a bluish color - but has a characteristic odor similar to that of bleach at a concentration of 0.01 ppm.
Although it appears unstable and tends to decompose into oxygen, ozone is naturally present in the Earth's atmosphere. In the upper atmosphere, the stratosphere, it forms what is called the ozone layer that protects the Earth from most of the sun's ultraviolet radiation. We are talking about good ozone. Some gases, such as CFCs - including chlorofluorocarbons - have the unfortunate tendency to catalyze the transformation of ozone into oxygen. This is the origin of the famous hole of the ozone layer.
