Everything Kids' Astronomy Book Read Online Free PDF Page A

found it? Some people like to try and find the pieces of a meteorite if they can tell where a big one has fallen. They organize hunts and will sometimes let volunteers help them look. The hunters can learn where the meteorite came from by having an expert check it out. Most of them are made out of metal or stone, just like the rocks here on Earth, but they were created when the solar system was forming. They can come from other planets, the moon, and asteroids. Keep watching the skies and maybe you will get to help look for one. If you think you see one, be sure to tell your family and have them help you watch it. To learn more about meteorites, type in “museum & meteorites” to see pictures of them and a list of natural history museums that display them.
    WORDS to KNOW
    METEORITE: The objects that fall from space onto the earth are called meteorites. When they start to burn in the sky, they are sometimes called falling stars.
    COMET: A comet is an object that appears to have a glowing tail as it travels through space. One famous comet is Halley’s comet, known for its timely return trips
    Just for Fun
    Comet Balls
    To make a comet ball all you need is a soft rubber ball or tennis ball, and some cloth ribbon or strips of cloth to use for its tail. Have an adult help you make a hole in the ball, and then push the ribbons into it or use duct tape to fasten the ribbons on it. Now toss your ball through the air.
    What’s in a Name?
    What’s another name for a large meteor? Are they just small asteroids that have entered Earth’s atmosphere? Some astronomers call Ceres a planetoid or a minor planet because of its size and the fact that it orbits the Earth. In astronomy’s constantly changing vocabulary, today it might be called a small dwarf planet! What do you think Earth Grazers (EGAS) would be? If you said it’s just another name for the near-Earth asteroids, you’re right. Just to make it more confusing, some people also called the meteors that skim the top of the atmosphere and leave a long, glowing line the same thing. Have you heard the word binary, which means two of something? Astronomers use it when they are talking about stars, but there are also binary asteroids. When two people are born at the same time, we call them twins, even if they don’t look exactly the same. The same is true for binary asteroids. Some of these asteroids have satellites that make an orbit around them just like our moon does around Earth! So when is a moon not a moon? Would you believe that many of the moons in the solar system are actually captured asteroids? Many of them are very small, have weird shapes, and travel backwards as they circle their planets. Many of the moons located in Saturn’s rings are so small that they aren’t called moons anymore; they’ve been downgraded or reduced in name to moonlets!

    A Tale of a Tail
    Have you heard of Halley’s comet? It has made an appearance in Earth’s solar system at around 76 year intervals for more than 2000 years! Do you know that you can actually see the orbit of the comet as it moves slowly across the sky, goes behind the sun, and appears again? This huge, dirt-filled snowball can’t be seen when it starts the long journey at the edge of the solar system until the sun reflects off of it, just like the earth and the moon. Its long tail stretches across many millions of miles of the night sky as it is pushed away from the sun by the solar wind. Although the comet appears to be on fire, when its glowing tail passed over Earth in 1910 no one was injured. Some passing comets with longer orbits may not be seen again for hundreds of years and some never return. Would you like to have a space object named after you? Comets are usually named after the first person that discovered them. If you want to find your own comet, scan the skies and look for a fuzzy patch of light that seems to be in a slightly different area of the sky each