If you've ever spent much time in American farm country, then you've probably noticed that there's a strong tradition there of coating barns and outbuildings with red paint. Why?
Because nuclear fusion.
Okay, the actual answer is simply because red paint has long been a cheap color to buy. But, explains Google engineer Yonatan Zunger, there is some really interesting physics lurking in the background of that price point.
What makes a cheap pigment? Obviously, that it’s plentiful. The red pigment that makes cheap paint is red ochre, which is just iron and oxygen. These are incredibly plentiful: the Earth’s crust is 6% iron and 30% oxygen. Oxygen is plentiful and affects the color of compounds it’s in by shaping them, but the real color is determined by the d-electrons of whatever attaches to it: red from iron, blues and greens from copper, a beautiful deep blue from cobalt, and so on. So if we know that good pigments will all come from elements in that big d-block in the middle, the real question is, why is one of these elements, iron, so much more common than all of the others? Why isn’t our world made mostly of, say, copper, or vanadium?
The answer, again, is nuclear fusion.
You can read the full story on Zunger's Google+ page. In my experience, white is another really common barn color, due to the fact that whitewash — a paint made from calcium hydroxide and chalk (which is also calcium) — is way cheap, as well. Calcium is also one of the most abundant elements in the Earth's crust ... clocking in at number 5, right under iron in the top 10. I'm sure there's some different science that accounts for the high concentrations of calcium on our planet, but the same principal applies. Cheap paint is paint made with abundant (and easily accessible) elements. And abundant elements happen because of physics.
Image: Red Nebraska Barn, a Creative Commons Attribution No-Derivative-Works (2.0) image from 50779843@N03's photostream
To demonstrate the Magnus effect, YouTuber PeterSripol grabbed a couple of KFC buckets and tricked out an RC plane. The resulting trial and error is mostly the latter.
One of the weirdest places in Antarctica is Blood Falls, a five-story cascade of blood-red liquid pouring from Taylor Glacier. Researchers finally traced its source: a saltwater lake millions of years old trapped under the glacier.
Fetal lambs survived for weeks in an experimental artificial womb, and scientists hope that the breakthrough could lead to new treatments for premature babies and perhaps the dreamed-of machine utopia where humans are kept mindlessly writhing in translucent plastic sheaths filled with psuedoamniotic liquid. Physicians at the Children’s Hospital of Philadelphia placed fetal lambs into […]
If you want to work in tech, but don’t have any desire to code web apps to help businesses sell things to other business, you might want to consider a career in cybersecurity. Judging from the apparent complete infiltration of Russian hackers in American cyberspace, it seems fair to speculate that there’s a major shortage of […]
All moms are different. But all moms like getting flowers on Mother’s Day, and that’s a fact (not, however a fact we can document in any fashion.) Instead of getting chewed out for forgetting to call her on the second Sunday of May, you can take care of it ahead of time with Teleflora’s flower […]
Yeah, Bluetooth audio is pretty common these days, so why should you care about these earbuds? Look how happy that woman up above looks. She’s got FRESHeBUDS in. Boom. There’s your reason. She’s also at the beach and it appears to be a very nice day.But for the sake of promotion, wireless earbuds are fast becoming the […]