Things we don not know for sure – how it’s happening, how was created, how it is. Questions that people do not know the answer!

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Prairie Potholes - natural depressions formed by glaciers

Natural wetlands in the upper U.S. and Canada - known as prairie potholes. These natural depressions formed thousands of years ago by glaciers that scraped over that part of North America. The potholes themselves come in a variety of shapes…
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Glacier Lake Floods

Glaciers in the mountains of India, Nepal, and Tibet are melting . . . Lakes sometimes form on top of the glaciers. When they grow too rapidly, they burst over natural rocky dams and surge down river valleys -- with the potential to destroy…
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The Same Moon

We recently recorded this question. Melissa: Hi, my name is Melissa and I'm from Chicago, Illinois, and my question is: if I'm living in California and I'm talking to a friend in New York City, and we look at the moon at the same time, does…
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How is wind chill calculated?

Our bodies emit heat that normally stays in a thin envelope of warm air all around us. When the wind whisks away that warm layer, we lose heat faster -- and that's wind chill. The formula calculates the relationship between wind speed, air temperature…
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Coral and Sea Level

Emma-Kate Potter is a PhD candidate at the Australian National University. She tracks the history of sea level changes by studying growth cycles of ancient coral. Emma-Kate Potter: So in the past, sea level has gone up and down, and up and…
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Scientist explains warming link to hurricanes

Not all scientists agree, but some studies indicate global warming is changing the intensity of hurricanes. Kevin Trenberth is one whose research indicates this connection. Trenberth is head of the Climate Analysis Section at the National…
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Scientists turn weapons into tools

The U.S. military uses small, remote-controlled airplanes for combat and spying. These are called uninhabited aerial vehicles, or UAVs. But Frank Cutler and his colleagues see a whole new use for these aircraft. Frank Cutler: . . . we're…
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Key to coping with uncertainty: be flexible

Some of society's biggest challenges -- such as climate change, global health and terrorism -- are also the hardest to overcome because of uncertainty about the future. Steven Popper is an economist at the RAND Corporation. He uses computer…
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Basking Sharks

Basking sharks are found in temperate coastal waters across our planet. These sharks are big -- second in size only to whale sharks. In summer, they're easy to spot, swimming lazily at the ocean surface. But every winter basking sharks just…
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What is a "glory?"

How does the bright 'rainbow appearing' ring that appears with of a shadow of a large jet form on the clouds below? That colored ring is called a glory. Glories are commonly seen while you're traveling by airplane near the level of the clouds.…
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About nanotechnology - what exactly is it?

Nanotechnology involves working with extremely small things -- things that can be measured in nanometers. A nanometer is one millionth the size of a pinhead. That's also about the width of ten hydrogen atoms laid out side by side. Scientists…
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GPS Limb Sounding

Scientists at the Jet Propulsion Laboratory have found they can use orbiting Global Positioning System or GPS satellites to monitor weather. In the same way that light bends, or refracts as it enters water, the radio signals from these satellites…