MARY LOUISE KELLY, HOST:
There is good news in the universe, says astrophysicist Adam Frank. In fact, it is the universe, and how you are part of it. Just lean back. Take a look at the sky - the clouds, in particular.
ADAM FRANK, BYLINE: So what did you see in those clouds? Was it a bunny rabbit, or maybe a dragon? No matter what caught your imagination in those cloud shapes, they all point back to something truly extraordinary about the universe - it's ceaseless power of creative transformation.
See, every cloud is really a transformation engine. Clouds are made of water droplets or ice crystals, and they're moving in the sky. Even a small cloud can hold the same weight in water as 400 elephants. That's pretty amazing on its own. But you got to ask, how did those elephants - I mean water - get up there, and why did they turn into a cloud?
When the ground warms up, it makes nearby air rise. That air will include some water in the form of a gas we call water vapor. Think of steam coming out of a teakettle. But as the air rises into the sky, it gets colder. And that's the first step that gets the transformations going.
When the temperature gets cold enough, some of that water condenses. That means the water molecules stop acting like a gas. They stop bouncing around like drunken dancers in a mosh pit and drop into the more packed and orderly state of liquid drops or ice crystals. Scientists call this a phase transition, and it's at that moment that the cloud appears. But that's not the end of the story.
Phase transitions transform matter and energy, carrying it from one form into another, like water into gas. When the water condenses, it actually releases heat back into the air. And this new heat makes the air buoyant, like a balloon underwater, so now the air wants to rise even more.
So making those drops also makes motion. But the new motion quickly turns turbulent, as one blob of air slams into the next one nearby. And these swirly, turbulent cloud motions mix the cloud with dry air so that the water that had been turned from a gas into a liquid gets phase transitioned back into a gas. What the cloud maketh, the cloud taketh away.
This dance of constant transformation - gas into liquid and heat into motion - that's what gives clouds their ever-changing, infinitely variable shapes. The choreography of matter and energy shifting from one form to another is proof, right up there in the sky, of nature's infinite creative capacity. The transformation shows how nature innovates. And most importantly, these transformations matter because you're part of them.
Inside your lungs, inside your belly, inside your brain, the universe is carrying out a thousand, thousand different kinds of transformations of matter and energy. The oxygen gas you breathe gets bound up into red blood cells to be carried throughout your body. The water you drink gets split up into ions that drive biochemical machines. The food you eat powers the thoughts that fill up your head - you know, thoughts like, hey, that cloud kind of looks like a bunny.
So you, too, are an expression of nature's infinite capacity for originality and innovation. And that is the deep, resonant and ever-present connection between you, the cloud, the imaginary bunny and the universe that made them all.
KELLY: The universe also made Adam Frank. He's a professor of astrophysics at the University of Rochester and author of "Light Of The Stars: Alien Worlds And The Fate Of The Earth."
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