NASA, short for The National Aeronautics and Space Administration is is an independent agency of the executive branch of the United States federal government responsible for the civilian space program, as well as aeronautics and aerospace research. But, it does a lot more than that, and in fact a few decades ago, NASA saved our very planet.
In the early eighties, unknown to most people, our planet was headed towards disaster. By 2165, the world as we know it today would’ve been destroyed. Crops and livestock farming would be failing, leading to food shortages. Cancer rates would be much, much higher than the present day, and stepping outside for even 5 minutes could have meant getting sunburned severely. Luckily, NASA stepped in.
NASA studies the earth, how the environment works, and checks if everything is normal. In 1985, things were not looking very good. Teams from NASA and the British Antarctic Survey discovered that a portion of the earth’s ozone layer, over Antarctica, was damaged. This gave rise to the term ozone hole. The ozone layer absorbs harmful UV rays that are emitted from the sun and prevent them from reaching the earth. From September through November 1985, the level of ozone in the ozone hole dropped by around 67%.
NASA had a good idea of what was happening, and chlorofluorocarbons (or CFCs) were to blame. CFCs are a group of fully halogenated hydrocarbons (containing carbon, chlorine and fluorine) derived from lower alkanes. Commonly known as Freons, these are found in aerosol cans, refrigerants and are also used as solvents. They were being used industrially as they are non toxic to humans, but they can also break down ozone easily.
When UV light shines on a CFC molecule, a chlorine atom breaks away, attacks an ozone molecule and breaks it down into oxygen molecules. When the ozone in the ozone layer turns into oxygen, it loses the UV light trapping behavior. Chlorine atoms are also more destructive to ozone in cold temperatures, which explains why the ozone layer depletion started over Antarctica.
If we had continued using CFCs, 17% of the ozone layer would have been gone by 2020. By 2065, the UV levels on earth would have doubled, and life on earth would have been extremely difficult. Scientists across the world decided to ban CFCs. The Montreal Protocol was signed in 1987, lowering their production and by 1996, they were completely banned in most developed countries. However, all hope is not lost, as newer data shows that the ozone hole is diminishing, and could be gone by the end of the century.