Innholdsfortegnelse for March 2015 i Ask Science and Arts Magazine for Kids and Children

Funny Money There will soon be a new way to tell if that dollar bill you are about to spend is counterfeit: just blow on it. And scientists are thanking longhorn beetles for the idea. When the air is damp, their wings change color from gold to red. This happens because water vapor causes tiny particles in the beetles’ wings to thicken and reflect light differently. Now scientists have made ink that does the same thing. Paper money printed with the new ink can change color or reveal patterns with the dampness of a human breath. Fraudsters trying to make fake money will find the technique almost impossible to copy. A wet Tmesisternus isabellae beetle changes color from gold to red. NOISE DRIVES BATS BATTY In the wilds of northern…

Telescopes on Earth are looking for exoplanets in other ways. On top of a volcano in Hawaii, the twin Keck telescopes take pictures of the same star at different times, to see if it wobbles. Even though stars are much bigger than planets, planets also have gravity. As a planet circles around a star, the planet’s gravity pushes the star back and forth just a tiny bit. The amount of wobble helps scientists figure out if a planet is there and how big it is. Yet another method looks for faint double-images of a star caused by light bending around a planet we can’t see.…

Did life on Earth actually come from space? Some astrobiologists, scientists who study life in space, think it’s possible. This doesn’t mean that humans, or even dinosaurs, arrived from space— any space colonists would have been tiny microbes that arrived a long, long time ago. We know that microbes have been living on Earth for at least 3.5 billion years. But other planets may also be home to tiny creatures. Back when Mars and Earth first formed, they were both too hot for any living things to survive. Smaller Mars cooled faster, so it might have had life before Earth did. How would Mars microbes get to Earth? They might have hitched a ride on a meteorite, a rock that lands on Earth from space. Some meteorites come from Mars.…

If When we discover life beyond Earth, what will it look like? For this month’s contest, imagine a world far from Earth, and draw us a picture of the strange and amazing creatures that might live there. Send us your spectacular spacelings, and we’ll host an alien invasion in an upcoming issue of Ask. Contest Rules: 1. Your contest entry must be your very own work. Ideas and words should not be copied. 2. Be sure to include your name, age, and full address on your entry. 3. Only one entry per person, please. 4. If you want your work returned, enclose a self-addressed, stamped envelope. 5. Your entry must be signed or emailed by a parent or legal guardian, saying it’s your own work and that no one helped…

Living things do some things that non-living things don’t do: • Move on their own • Eat • Excrete (Poop) • Breathe • Reproduce • Sense and respond to their environments • Grow, change, and die s k Rocks grow and change, but they don’t eat or move on their own, so they aren’t alive. But even with this list, scientists can’t always agree. Viruses, for example, seem to be alive in some ways, but not in others. Scientists are still debating whether they belong on the tree of life.…

Microbes are tiny life forms like bacteria and fungi that you can only see through a microscope. Sometimes microbes gather into a sheet held together with slippery goo. The goo protects the microbes, like armor, and helps them cling to things. The goo and the microbes together are called a “biofilm.” There are channels in the goo, a bit like streets. They allow the microbes to share food and water and pass wastes out. Cave snottites are a particularly impressive kind of biofilm, but biofilms are found everywhere. The plaque that forms on your teeth is a biofilm, and so is sink slime.…

Dear Bot, Do you like space? I do. I like space because each planet is different. I was wondering if you would tell me a little more about space. What is your favorite planet and why? Maddy T. Oregon Dear Maddy, I hope you have as much fun with this issue as we did making it! I love space because there is so much to explore. Including many more different planets than we ever imagined. I’m not sure I can pick my favorite planet—every day, they find a new one! But Earth is very nice too. Bot Dear Marvin, You are so funny, clever, and resourceful! I like your practical jokes. Have you ever thought of flour on the fan? It’s messy. Calvin L., age 10, Wisconsin Dear Calvin, I…

Really big! On Earth, a long trip might be many miles or kilometers. But stars in space are SO far apart that astronomers measure the distances in light years, which is how far light can travel in a year. Light zips along at 186,000 miles per second. How fast is that? Snap your fingers. If you were light, you could have circled the Earth 7 1/2 times! Even at that fantastic speed, it takes light 100,000 years to cross our galaxy. And our galaxy is just one of hundreds of billions of galaxies that stretch across the universe. The farthest galaxies that we can see in every direction are about 13.7 billion light years away—but that doesn’t mean there’s no universe beyond that. It just means we can’t see it.…