Innholdsfortegnelse for July/August 2017 i Muse: The magazine of science, culture, and smart laughs for kids and children

. . . Because it didn’t care that there was a car coming! City animals are often in danger of getting squashed by traffic. But if they watch lots of cars, trucks, and buses speed past, maybe they learn to keep their distance. Scientists tested pigeons to find out if this is true. They used birds that had grown up in a barn and never seen traffic. First, the researchers put the pigeons in cages next to a road and zoomed past them in a pickup truck, over and over. Then they tested the birds in a virtual traffic simulation. The pigeons watched a video of a truck that looked like it was about it hit them. Researchers measured how quickly the pigeons got scared and flew away. Pigeons that…

The armies battled beneath the hot sun. Neither side seemed to be winning. It was May 28, 585 BCE, the sixth year of war between the Lydians and the Medes in what is now Turkey. Suddenly, the light grew thin and the air turned cold. A hole appeared in the sky where the sun should be, surrounded by a halo of light. Surely this was a sign from the gods that they should make peace. A total eclipse of the sun, as those ancient armies witnessed, could be frightening if you didn’t know it was coming. That fear could even stop a war! Nowadays, we know what causes eclipses. We can predict when and where they’ll happen, down to the minute and mile. Instead of frightening people, an eclipse can…

If you’re under 20, NASA’s Cassini spacecraft has been in space your whole life. If you’re under 13, Cassini has been orbiting Saturn your whole life. Thi robotic spacecraft is about a billion miles (1.6 billion km) from Earth, learning about Saturn’s rings and moons, watching its storms, and measuring its moons. Scientists have lots of questions about Saturn. Why does Saturn have massive storms that last for months or years? How old are its rings, and how were they formed? Could any of its moons support life? NASA’s Cassini spacecraft is helping scientists answer these questions, and many more. A SPACECRAFT WITH A SPECIAL BLANKET As big as a school bus, Cassini is the largest interplanetary spacecraft that NASA has ever built. Cassini’s shiny gold-colored foil blanket protects the…

On a clear night, away from city lights, you can see a sky packed with stars. But you can’t see planets orbiting any of these stars, even with the strongest Earth-based telescopes. Planets are smaller than stars and don’t give off heir own light to make them visible. Astronomers reported the discovery of seven Earth-sized planets orbiting a nearby star called TRAPPIST-1 in February 2017. They had to rely on indirect evidence to tell them that the planets are there. By doing some math, they figured out the number of planets and the distance of their orbits. TRAPPIST-1 is a red dwarf star, just a fraction of the size of our own sun and only a bit larger than Jupiter. If the sun were the size of a basketball, TRAPPIST-1…

In a forest in southwestern India, researchers discovered a new species of spider. The little brown critter has spiny legs and a pointed back that looks like a dead leaf. This helps it stay camouflaged during the day. But the spider’s odd shape didn’t only remind the scientists of a leaf. They also thought it looked just like the “sorting hat” from the Harry Potter books. In J. K. Rowling’s series, every new student arriving at wizarding school has to put on this magical hat. Then the hat announces which of four houses the student belongs in. The hat’s original owner was school cofounder Godric Gryffindor. So the scientists named the new spider Eriovixia gryffindori, in honor of the books they love—and the magical world of real-life bugs. One of…

A CENTRIFUGE (SENT-ruh-fyooj) is a basic tool in medical labs. It’s a machine that spins very quickly. When doctors spin a tube of blood in a centrifuge, the blood separates into different components, like salad dressing before you shake it up. This lets doctors examine the blood or test it for diseases. But these expensive tools are hard to get in some parts of the world. Now researchers have come up with a (very) cheap solution, based on a classic toy. The team got inspiration from a toy called a whirligig or buzzer. It’s a disk or button that spins on a loop of string. Kids around the world have played with these for thousands of years. The new “paperfuge” holds tiny tubes on a disk made of paper. When…

I saw my first solar eclipse as a college freshman 57 years ago, from an airplane over the Atlantic just off the Boston coastline. Since then, I’ve seen 64 additional solar eclipses. My interest in studying the sun at eclipses has taken me all over the world. I’ve seen 33 total eclipses so far, from the Arctic, from an airplane overflying the Antarctic, from Africa, North America, South America, Asia, and Europe. And from some mid-ocean islands and ships. But I have never seen a total eclipse from the United States mainland. To be outdoors as the universe around you darkens, with the light turning eerie and shadows sharpening in a way that makes you uneasy, is the most remarkable experience I have ever witnessed. So I am very much…

Could anything be more amazing than seeing a total solar eclipse? How about seeing that eclipse from space? Peering down miles above the Earth (higher than the clouds), you would see not only the moon crossing the face of the sun, but also the shadow of the moon racing across oceans and continents, silhouetted against the blackness of space and the curving horizon of Earth. But you’d need to be an astronaut to see something like that, wouldn’t you? Not anymore. On August 21, 2017, hundreds of young people will see it too. And they’ll share it with the world in near real time. Welcome to the amazing Eclipse Ballooning Project, in which teams of students across the United States will launch devices high into the air to observe the…

The Cassini spacecraft, seen above in an artist’s concept, was named after a French-Italian astronomer. Jean-Dominique Cassini studied Saturn in the seventeenth century. He discovered several of Saturn’s moons (Iapetus, Rhea, Tethys, and Dione) and was the first person to observe the large gap in Saturn’s rings that eis now named after him—the Cassini Division. Cassini takes pictures in black and white. By putting red, green, and blue filters in front of the camera lens, computers can help create a color picture from these black-and-white images. Cassini also has special cameras that can see in infrared and ultraviolet, beyond the visible range the human eye can see. This false-color view of clouds in Saturn’s northern hemisphere results from combining images from Cassini’s camera. The farthest astronauts have ever gone in…

Nicknamed “the thunder lizard,” the Brontosaurus was one of the largest animals to ever walk the Earth. Then one day the Brontosaurus just vanished. This wasn’t another extinction. This time around, Brontosaurus fell victim to a naming glitch. Scientific tradition dictates that when a new organism is discovered or identified, it’s assigned a two-word Latin name. For example, Homo sapiens is the fancy name for a human. This naming device is called the Linnaean System, named for its originator, the eighteenth-century naturalist Carl Linnaeus. Brontosaurus is a genus, or group of closely related species, first identified in 187 A similar genus called Apatosaurus was identified two years earlier. During the 1900s, paleontologists reviewing the evidence concluded that Apatosaurus and Brontosaurus are actually the same genus. Since scientists named Apatosaurus first,…

SUNSPOTS are magnetic storms. They look dark because they’re cooler than the photosphere. They can be 10 times the size of Earth. FILAMENTS are squiggles of cool gas in the chromosphere. A CORONAL MASS EJECTION (CME) happens when gas blasts off the sun’s surface at 186 miles (300 km) per second. If a CME hits the Earth’s atmosphere, we see the beautiful aurora, also called northern and southern lights. PROMINENCES are filaments see from the side. During an eclipse, they look like red loops sticking out from behind the edge of the moon. [INSIDE THE SUN] CORE 27 million 0  F (15 million0 C) ➜ The sun is powered by nuclear fusion. In short: hydrogen atoms smash together to make helium atoms. Each helium atom has a…

Q: If the universe keeps expanding, what is it expanding into? —Aiden K., Ohio A: In 1929, the astronomer Edwin Hubble made an unexpected discovery. When he looked through a telescope at faraway galaxies, he noticed that they appeared to be moving away from Earth. And the farther away the galaxies were from him and his telescope, the faster they seemed to be traveling. That observation is neatly summed up in the statement “the universe is expanding.” But “expanding” isn’t really the right word for what’s going on, says Mario De Leo-Winkler, an astronomer at the University of California, Riverside. Th nk of a deflated balloon. As you blow it up, the balloon gets bigger and occupies more and more space. Space that was once outside the balloon is now…

As you read this, an asteroid almost a third of a mile (one-half kilometer) in diameter is hurtling toward Earth. And a spacecraft is hurtling toward that asteroid. It’s all part of a mission to take a sample of that asteroid and return it to Earth. Scientists say this sample could offer us important clues about how our planet developed—and how life formed here. But to get this right, scientists have to ensure that everything about this seven-year mission goes smoothly. First up: a navigation maneuver near Earth. Final Rendezvous with Earth In late September 2017, the spacecraft, called OSIRIS-REx, will pass by the Earth for the final time. (Its full name is Origins Spectral Interpretation Resource Identification and Security-Regolith Explorer. No wonder it goes by a nickname.) The reason…

AN ASTEROID impact likely wiped out the dinosaurs. Could another one obliterate humanity? The risk of a large asteroid slamming into Earth during your lifetime is relatively low. You have an estimated 1 in 75 million chance of dying in such a catastrophe. A fireworks accident (1 in 50 million), a bee sting (1 in 25 million), or a lightning strike (1 in 10 million) is more likely to take you out. Despite the long odds, astronomers and scientists keep an eye on the sky for nearby objects that might pose a threat. Now, thanks to technology, you can join them. The free AsteroidTracker app for iOS and Android keeps you up to date with news about all known objects from space that will pass near Earth. You can also…