Barns Are Painted Red Because of the Physics of Dying Stars

http://www.smithsonianmag.com/smart-news/barns-are-painted-red-because-of-the-physics-of-dying-stars-58185724/?no-ist
I like articles such as this one that take mundane phenomena and link them to the stars. Though worth a read, punchline / TL;DR of this is that nuclear fusion stops generating excess energy at iron and this leads to an abundance of iron seeding the universe following supernovae, finding its way to rocky planets such as ours. Thus, iron oxide is plentiful, cheap, and just happens to make red paint.