We owe a lot to the sun. Without it, we’d have no heat or light, of course. We’d also have no photosynthesis, and thus no oxygen, without which, neither we nor Earth’s ozone layer would exist. And yet, as a giant nuclear reactor, the sun insists on bombarding us with energy that, left unchecked, could burn all of us to a crisp. And the ozone layer has never been a foolproof filter when it comes to screening out harmful ultraviolet (UV) rays.
Even in ancient times, before humans could generate enough ozone-depleting substances to erode that protective barrier, the ozone layer still let enough solar radiation through that our ancestors had to deal with sunburn and other sun-related damage — just as we do today.
In modern times, of course, we’ve developed preventive measures — apparel and accessories designed specifically to minimize UV exposure, as well as topical sunscreen and ...
