Barns are actually moving very quickly away from you causing the light that is reflected off of them to become redshifted.
DA RED WUNZ GO FASTA
Actual answer: back in the day the sealant that farmers coated barns with often had iron oxide in it because it helps prevent rot and mold, and the iron oxide would turn the sealant mixture red. Now people just do it because it’s a tradition.
It also happens to be cheap. Other pigments are hard to manufacture. Rust is easy.
Even today red paint is sometimes cheaper, especially when ordered in bulk.
Farmers originally used to seal their barns with a combination of linseed oil (red-ish) and iron oxide (rust, red). Then when paint came around, apparently red paint was the cheapest. https://www.bobvila.com/articles/solved-why-are-barns-painted-red/
Idk if this is true for the US but where I live in Scandinavia red is a common house colour because historically it was a cheap colour you could get from mixing red ochre and oil, so red barns aren’t uncommon. Then again the US midwest does have a lot of Scandinavian immigrants so it might’ve bled over culturally because there’s lot of farms up there?
Red is the traditional color of painted wooden structures pretty much everywhere, think of Chinese temples for example. Black tar is another common one. Cave paintings typically used red too.
Barns are red because of exploding stars - https://www.smithsonianmag.com/smart-news/barns-are-painted-red-because-of-the-physics-of-dying-stars-58185724/
Great article. Similar to “NASA’s booster size is the result of the size of a horse’s ass”: https://www.linkedin.com/pulse/4-feet-85-inches-space-shuttle-horses-ass-william-batch-batchelder
I love these types of articles. I feel like there should be a community for these, but I don’t know what it’d be called
That is because red paint was inexpensive and abundant, than it became tradition.