The ozone layer absorbs ultraviolet radiation that can be very harmful to all forms of life. In 1974, however, scientists discovered that chlorofluorocarbons (CFCs), a chemical used in aerosol sprays, refrigerants, and the creation of synthetic materials, break down when they enter the stratosphere, and produce a chlorine atom, which then contributes to breaking down the ozone layer. In 1985, British Antarctic Survey scientists discovered a massive hole in the ozone layer above Antarctica.
In the 1940s, Nazi Germany under the government of Adolf Hitler was advancing its conquest of Europe during the Second World War. By May 1940, Luxembourg, a small neutral country bordering Germany, was placed under military occupation by forces of the Third Reich. The meager resistance made by local police forces and customs officers at the border crossing was quickly crushed by the German Wehrmacht, the unified armed forces of Nazi Germany.