A movie of how ozone is made from oxygen

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Ozone is made up of ordinary oxygen, just like what we breathe. The only difference is that ozone is made up of three oxygen atoms, while the stuff we breathe (molecular oxygen) is made up of only two atoms. Solar rays high in the atmosphere convert O2 to O3. In the upper atmosphere, rays from the Sun break a normal oxygen molecule into two separate oxygen atoms. Another oxygen molecule then picks up one of these atoms to form an ozone molecule.


For more info: http://daac.gsfc.nasa.gov/CAMPAIGN_DOCS/ATM_CHEM/ozone_atmosphere.html