This video—taken by the Ozone Monitoring Instrument onboard NASA's Aura satellite—shows the ozone hole as it reaches its yearly maximum, 23 years after the ban of chlorofluorocarbons, once the heart of all fridges and hair spray cans worldwide.
Today is the International Day for the Preservation of the Ozone Layer, which marks the day of the ban: September 16, 1987. The effects of chlorofluorocarbons and other chlorine and bromine-containing compounds are still being felt on Earth's atmosphere today.
Chlorofluorocarbons—or as the DuPont Corporation called them: Freon—is an almost miraculous organic compound that had low toxicity, low reactivity, and low flammability. They were thought to be good for the environment until two researchers at the University of California, Irvine, discovered they were silently destroying the planet.
Sherwood Rowland and Mario Molina found that CFCs were decomposed by the Sun's light once in the upper atmosphere layer, producing a chlorine radical that turns ozone into O2, destroying the layer that protects us and the planet against sure death by ultraviolet rays.
In other words: If you were planning some chilly vacations in Antarctica, cancel them. [NASA Goddard—Thanks Rebecca!]