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Bacterial melanin clothes may protect us from UV rays in the future - Yanko Design
(www.yankodesign.com)
Technology for a Solar-Punk future.
Airships and hydroponic farms...
A cotton t-shirt has a SPF of about 6. It will help, but we can do better, even without melanin-infused clothing.
There are also UV transparent bikinis, for tanning without tan lines or nudity.