We're putting lots of transition metals into the stratosphere. That's not good.

We successfully plugged the hole in the ozone layer that was discovered in the 1980s by banning ozone-depleting substances such as chlorofluorocarbons (CFCs). But, it seems we might be unintentionally creating another potential atmospheric calamity by using the upper atmosphere to destroy huge constellations of satellites after a very short (i.e. 5 year) lifetime.