How did the ozone form?

Answer 1

The ozone is formed and destroyed from the same radiation i.e the ultraviolet radiation. The oxygen present in the stratospheric region of the atmosphere when comes in contact with the high energy ultraviolet radiations of the sun it breaks down into 2 molecules of nascent oxygen. These 2 molecules then combine individually with oxygen molecule in the presence of these radiations and thus form a molecule of ozone. Moreover the ozone is also formed during the lightning. The concept of making artificial ozone is based on this principle of passing electricity to form ozone.

Answer 2

Ozone is formed in the Earth's stratosphere by the interaction of ultraviolet (UV) radiation from the sun with oxygen molecules. UV radiation breaks apart oxygen molecules (O2), and the free oxygen atoms then combine with other oxygen molecules to form ozone (O3).