Earth
The deepest place, the driest place: the extremes of the planet under our feet.
32 articles
What’s the difference between magnitude and seismic intensity?
Two numbers come up in every earthquake report. They look alike, but they actually measure completely different things.
How hot is lightning?
For the briefest instant, a single streak of light carves a path hotter than the Sun. And that deafening roar comes from the very same heat.
Why do volcanic eruptions make lightning?
Bolts of lightning flash through a towering black plume of ash. There is no thundercloud, so why does lightning strike above a volcano? The phenomenon appears even in Japanese records from the eighth century.
Is it true that no two snowflakes are alike?
“No two snowflakes are alike,” people say. But has anyone actually checked? Each flake, it turns out, carries a record of its journey through the sky.
Why do auroras glow?
Curtains of light rippling across the night sky. We think of them as a polar sight, yet they were recorded in Japan as far back as the seventh century.
What is the deepest place in the world?
Sink Mount Everest whole and its summit would still lie far below the surface. Fewer people have visited Earth’s deepest spot than have gone to space.
Why are rainbows round?
A rainbow in the sky is always a half circle or a smaller arc. But that shape is only part of the picture. Where did the rest of the rainbow go?
How thick is the ice in Antarctica?
Antarctica, the white continent. How much thickness lies hidden beneath its snow and ice? The latest map, built from some 60 years of surveys, also reveals surprising terrain under the ice.
How hot is the center of the Earth?
More than 6,000 kilometers beneath your feet lies a place no one has ever been. How did scientists work out its temperature?
What is the driest place on Earth?
In one corner of the ice continent lies a valley where even snow barely settles. And on the far side of the globe, a desert serves as a dress rehearsal for Mars.
Where is the rainiest place in the world?
Where in the world can you never put your umbrella away? In one place, more than 10,000 millimeters of rain a year has shaped the way people live.
What is the largest crystal in the world?
Deep in a mine, at the end of a freshly dug tunnel, miners came upon a scene straight out of a fairy tale. But it was not a place where anyone could stay for long.
What is the longest river in the world?
Your atlas has an answer. But some researchers aren’t convinced by it—because measuring a river turns out to be far harder than it sounds.
What is the largest lake in the world?
Look up “the world’s largest lake” in an atlas and you land on a slightly surprising name. The line between a lake and a sea is blurrier than you might think.
Is Japan moving?
The ground beneath our feet seems perfectly still. But measure it precisely, and the Japanese archipelago turns out to be on the move, a little every day.
Is Everest really the tallest mountain in the world?
There may be more than one answer to “What is the world’s tallest mountain?” Move the yardstick, and a different peak takes the throne.
Why is seawater salty?
River water isn’t salty. Rainwater isn’t salty. Yet the sea is. So where did all that salt come from in the first place?
Where did Earth’s water come from?
Oceans cover 70 percent of Earth’s surface. Where all that water came from, though, is one of the great open questions in science.
What is the longest cave in the world?
A labyrinth of darkness spreads beneath the ground. People have been measuring it for nearly 200 years, and there is still no end in sight.
How do tornadoes form?
A slender vortex reaches down from the sky to the ground. What conditions have to come together to create a tornado, the source of nature’s most violent winds?
Was the Sahara once green?
The Sahara, the world’s largest hot desert, is sand and rock as far as the eye can see. Yet beneath the sand and in the shelter of its rocks lie traces of a completely different landscape.
What is the largest island in the world?
Is Australia an island or a continent? To name the world’s largest island, you first have to answer a surprisingly tricky question: what exactly is an island?
Why is the sea blue?
The sea is blue because it reflects the sky—or so we’re often told. But when one scientist put that to the test aboard a ship, it turned out to be only part of the story.
Why is the sky blue and the sunset red?
Blue by day, red at dusk. It is the same sunlight all along, so why does the sky change color with the time of day?
Why do geysers erupt?
A quiet hole in the ground suddenly sends boiling water high into the sky, almost like clockwork. Behind the spectacle lies an underground “pressure cooker.”
How much does a cloud weigh?
Clouds look as light as cotton candy. If you could set one on a scale, how far would the needle swing? And why don’t clouds fall out of the sky?
Which is colder, the Arctic or the Antarctic?
Both are frozen worlds at the ends of the Earth. The two polar regions seem like twins, but what lies beneath their ice could hardly be more different.
What is the tallest waterfall in the world?
Somewhere, water plunges from a height far greater than Tokyo Skytree. And beneath the sea, an even bigger “invisible waterfall” is flowing.
When did Mount Fuji form?
Japan’s highest peak, a perfectly shaped cone. Beneath that elegant silhouette lie several “earlier Mount Fujis.”
Why do you float in the Dead Sea?
Lie back on the water and open a newspaper. A lake famous for photos like that lets even non-swimmers stay afloat. How does it work?
Why does singing sand squeak?
Walk along the beach and the sand squeaks under your feet. Beaches like this are scattered all over Japan. But this is very temperamental sand.
Is there a lake where the lightning never stops?
Silent lightning flickers on the horizon hundreds, even thousands of times in a single night. In one place, nights like that add up to months of every year.