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5 Ways Radioactivity Lights Up Your Life

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The word radioactivity always seems to bring up a number of glowing concerns. But maybe it's time you got over your fears and warmed up to the idea. Here are some reasons to grin about radioactivity.

1. If You Aren't Radioactive, You Just Ain't Livin'

The carbon dioxide in the air contains one part in a trillion of radiocarbon, which is radioactive and produced by cosmic rays from space. Plants, of course, take in this carbon, so then they become radioactive. If you eat plants or animals that eat plants, then you become radioactive. But why is this important? When you die, the radiocarbon will begin to decay. In 5,730 years half the radiocarbon will be gone. In another 5,730 years half of that will be gone. Because scientists can measure the age of ancient bones by measuring how much of the radiocarbon is gone, if a bone is not measurably radioactive, it means that its owner has been dead at least 50,000 years.

2. Radioactivity Helps You Get Your Drink On

The most surprising thing isn't that the Bureau of Alcohol, Firearms, and Tobacco tests alcoholic beverages for radioactivity, but that it rejects any alcohol that doesn't show radiation as "unfit." What's the reason? Any alcohol that has zero radioactivity must have come from very old carbon, and that usually means the alcohol has been manufactured from fossil fuels. After burial for 100 million years, the radio-carbon in the original organisms decays, and Congress has decreed that such alcohol may not be legally consumed. The argument that it's unfit probably has more to do with politics than with science, since there's no scientific reason why fossil fuel alcohol would be any worse than alcohol from grapes.

3. The Hills Wouldn't Be So Alive


Mountains come from the collision of large tectonic plates on the surface of the earth. Nobody knows what makes these plates move, but a reasonable guess is that the very slow flow of rocks (if they go slowly enough, they behave like fluids) is driven by the heat of radioactivity in the earth's depths. So, if it weren't for the fabulous effects of radioactivity, the plates wouldn't have moved, and those hills Julie Andrews and the Von Trapp family were so eager to sing about would never have existed.

4. You Might Be Speaking French

This is also related to the movement of the plates, discussed in the previous paragraph. About 100 million years ago, Europe and North America were one continent. And if you look on a modern map, you can still see how the continents once fit together. But the flow of rock, possibly driven by radioactivity, sent the continents apart. As a result, we have Europe and the United States. Why should we be thankful for radioactivity? Well, without it, the United States and France would probably be next-door neighbors, and Paris would seem a whole lot less exotic.

5. Ain't No Sunshine When There's No Radioactivity

The sun is driven by a process called fusion, which is actually a series of reactions that requires short-lived radioactive intermediaries to undergo a kind of radioactivity called beta decay. Simply stated, without radioactivity, the fusion on the sun could not proceed, and the sun would have cooled off billions of years ago. Needless to say, without the sun, plants and animals wouldn't be here, and you probably wouldn't have that killer tan.

Ed note: This article was pulled from Condensed Knowledge.

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United States Army // Public Domain
Watch Richard Feynman Explain Fire
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United States Army // Public Domain

Physicist Richard Feynman was a master explainer. His physics lectures are a model of clarity. His specialty is explaining one concept in the context of another concept the listener already understands.

In the video below, Feynman tackles the seemingly simple question: What is fire? This is a hard question for many of us to answer without referencing fire itself. Fire is burning. Fire is what happens when you light a match. Fire is a reaction. But aside from our existing knowledge of its effects (like flame), what is it and how does it happen? What else is fire like that we understand already?

In 1983, Feynman answered this question (among others) for the BBC on its Fun to Imagine series. He starts like so:

The atoms like each other to different degrees. Oxygen, for instance in the air, would like to be next to carbon, and if they're getting near each other, they snap together. If they're not too close though, they repel and they go apart, so they don't know that they could snap together.

It's just as if you have a ball that was [rolling and] trying to climb a hill and there was a hole it could go into. Like a volcano hole, a deep one. It's rolling along, and it doesn't go down in the deep [volcano] hole, because it starts to climb the hill and it rolls away again. But if you make it go fast enough, it'll fall into the hole.

So if you set something like wood in oxygen...there's carbon in the wood from a tree. And the oxygen comes and hits the carbon, but not hard enough. It just goes away again. The air is always [moving but] nothing's happening. If you can get it fast enough, by heating it up somehow...a few of [the atoms] come past, a few of them go over the top, so to speak.

So there you have it. If you understand what a volcano looks like and how a ball rolls under normal earth gravity, you have the start of this mental image for how fire works. Feynman's explanation manages to convey chemical behaviors in terms humans intuitively understand—the way a ball rolls—because that's the world we live in. Watch this for a delightful explanation:

The BBC has more clips (in better quality) at this slightly vintage website. You can also download the entire hour-long lecture from the Internet Archive.


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Wikimedia Commons // Public Domain
How Marie Curie Overcame the Odds and Won Two Nobel Prizes
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Wikimedia Commons // Public Domain

Marie Curie, born Marie Skłodowska, didn’t look like most scientists at the turn of the 20th century. In order to break into a field dominated by men, the French-Polish physicist attended a secret school in Poland and then studied in Paris, despite being unable to even afford food. Her persistence eventually paid off: Her radiation research earned her two Nobel prizes—one in physics and one in chemistry. While she opened doors for many brilliant woman scientists to follow her, she remains the only person, male or female, to win Nobel prizes in two separate sciences.

To learn more about the woman behind the groundbreaking discoveries, watch the animated video below from TED-Ed.


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