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What Is GRAVITY? There are forces working all the time. One of those forces is GRAVITY. Just like a force field, gravity is invisible, but it is very important. It is a force that pulls objects together. Gravity-defying materials don’t exist on Earth, but they do in the comics. Nth Every object has gravity. But the biggest, heaviest objects have metal, found on the planet the most gravity. The biggest object on Earth is . . . well, Earth. It Thanager, has the power to is Earth’s strong gravitational pull that keeps the moon orbiting around Earth. The sun’s gravitational pull is much stronger than Belts made cancel out gravity. Hawkman Green lantern’s of Nth metal and Hawkgirl wear belts power ring can Earth. It keeps Earth and the other planets orbiting around the sun. made of Nth metal. That’s why they can fly. create force fields.

The earth’s Gravity keeps moon in orbit 14 15

When you jump up, you always land back on the Super heroes are pulled by gravity too. When Superman leaps ground. Why? Because Earth’s gravity is pulling you over a huge building, he is eventually pulled back to Earth to it. Go ahead. Try it. Jump up up up as high as too. But he is so much stronger than the average person—and you can. You land back on the ground, right? he can fly—so Superman can jump up higher and stay in the air longer than other people or flying animals.

Up, Up and away!

and...even superman comes back to earth thanks gravity. 16 17 2D means something has two dimensions: length and width. In Can a Lasso Really Be Graphene is ultra-thin and made from pure other words, it is flat. carbon. At first, scientists created2D graphene. Then they formed 2D graphene into a sponge- 3D means it has three dimensions: length, UNBREAKABLE? like pattern to create 3D graphene. width, and height.

Wonder Woman’s Lasso of Truth An illustration of 3D graphene is incredible. It’s a weapon. And it protects anyone standing inside its loop. It can also force anyone to tell the truth. But it cannot be broken.

3D graphene is 200 times strongersteel! than

Scientists have not yet found a substance in real life that can make people tell the truth. But they have invented Now, a company is trying to create graphene rubber a nearly indestructible bands. Soon, there may be a substance just as stretchy material: GRAPHENE. and unbreakable as Wonder Woman’s lasso! 18 19

Yes! There are. (But don’t worry. Unless you are Real? mining deep in the Earth, climbing around volcanoes, or working with nuclear waste, you won’t stumble Is KRYPTONITE across them. Here are a few DANGEROUS MINERALS.

Just being near CINNABAR Kryptonite makes can be found near volcanoes and or hot springs. Superman weak. And, TORBERNITE is a rare bright green When it is heated up or disturbed, if he were exposed crystal found in some granite rocks. it can give off deadly mercury. to it long enough, it It can release a gas that can give could even kill him. people lung cancer. Kryptonite was formed by the radiation of his home planet Krypton when it exploded. But the planet Krypton and the dangerous rocks called Kryptonite only really exist in the comics. What about here on Earth? Are there rocks in nature that can be dangerous for you, like the radiation from Kryptonite For many years, people ground is dangerous to STIBNITE into a dark powder used as Superman? make-up. It was also used to make eating utensils. . . until scientists discovered it could poison people. 20 21

LILLY OF THE VALLEY: These Here are a few dangerous plants. innocent-looking bell-shaped flowers can cause dizziness, DEADLY? POISON IVY: Poison ivy is found in nausea, and vomiting. woody areas. Just brushing against Can Plants be it can result in a red, itchy rash

Poison Ivy is an expert with plants. She can make anything grow! Many of her plants are POISONOUS. They can cause itchy rashes, sleepiness, or even make it hard to move! When superheroes like Just like super heroes HYDRANGEA: In large amounts, MISTLETOE: Batman are exposed to This holiday favorite and super villains, some hydrangea flowers can become a can cause hallucinations! them, they get hurt. But plants have defenses. source of the deadly poison cyanide. is Poison Ivy’s villainous Poisonous plants have vegetation fact or chemicals in them fiction? that can make people Fact! Many plants or animals sick. If an in the real world have animal chews on a nasty effects. Poison poisonous plant and Ivy is named after a immediately feels ill, it common plant that will think twice before causes an itchy rash. ever chewing on that plant again. In this way, If you come across a plant in the wild that plants keep themselves you don’t recognize, don’t touch it! Better safe from harm. safe than sorry with these sneaky species. 22 23 Whenever you talk, you produce SOUND WAVES. Sound waves are a type Break Things? of pressure wave. You hear sounds when these waves reach your eardrum, VOICE which translates them into words, music, and other noises. Black Canary Can Your can produce a sonic scream, which is a high-powered wave of sound. A sonic wave is an incredibly powerful kind of pressure wave. The normal human body can’t produce high enough pitches to create this kind of wave. But that doesn’t mean it doesn’t exist! High-powered sonic devices have been used as burglar deterrents and by the military. In lab tests, scientists have even used sonic devices to temporarily disable people and, yup, to shatter glass.

wave shape for a low pitched sound

time wave distrubance

wave shape for a high pitched sound

Bad guys know to steer clear of Black Canary. Not only is she an expert in martial arts, but she also has a time super-powered voice. Black Canary uses her Canary Cry wave to break objects and startle enemies. Her scream is so powerful that it can stop villains in their tracks! distrubance 24 DO THIS: 25 activity Seeing the Invisible 1. Observe the clear nail polish in the bottle. What do you see? Many superheroes have powerful vision. They can see kinds of light that the normal human eye can’t see. But with a bit of experimentation, you too can see the invisible! 2. Brush some nail polish onto the black paper. Can you tell where the nail polish is?

3. Carefully drop a single drop of nail polish onto the surface of the water. Observe what happens. Can you see where the nail polish is? Does it look different than it did in the bottle or brushed onto the paper?

4. Use a strip of black paper to scoop up the nail polish. What does it look like? What colors do you see?

activity #1 What’s Happening? MATERIALS NEEDED Superheroes can see light at different WAVELENGTHS. And, with this experiment, so can you! Normally nail polish is a thick coating or film. But when you let a drop of it spread across water, it becomes a thin film. A thin film is only a few nanometers thick—that’s 10,000 times smaller than the thickness of your hair! The film is so thin that light can’t fully pass through it. Instead, it bounces off, causing the light to shift wavelengths ever so slightly. This slight shift causes you to see a rainbow of colors where there A bowl of clean Strips of sturdy black paper used to be only a clear film! Clear nail polish water