Exploring Space TABLE OF CONTENTS INTRODUCTION 3 ASTRONOMY Studying the Stars 6 UNIVERSE Infinite Space 8 Gravity The Invisible Magnet 10 Galaxies Star Clusters 12 Stars Distant Fire 14 Planets Wanderers in the Sky 16 Asteroids Minor Planets 18 Comets Rocketing Masses with Fuzzy Tails 20 SOLAR SYSTEM Family of the Sun 22 Mercury The Planet Nearest to the Sun 24 Venus A Morning and Evening Star 26 Moon A Trip to the Moon 28 Mars The Red Planet 30 Jupiter King of the Planets 32 Saturn The Ringed Planet 34 Uranus King George’s Star 36 Neptune The Eighth Planet 38 Pluto The Dwarf Planet 40 BIOGRAPHIES Aryabhata Ancient Mathematician-Astronomer 42 Nicolaus Copernicus Student of the Sky 44 Johannes Kepler Stargazer 46 Sir Isaac Newton An Apple an Idea 48 Albert Einstein A Brilliant Wonderer 50 Subrahmanyan Chandrasekhar Discovering How Stars Grow 52 Sally Ride First American Woman in Space 54 SPACECRAFT Exploring the New Frontier 56 Astronauts Going Up in Space 58 Extraterrestrial Life Life Beyond the Earth 60 GLOSSARY 62 INDEX 63 Brit a nnic a LEARNING LIBRARY
e Stars th g n S EA R C H LIG H T Which of these things do astronomers study stars planets moons astronauts comets Stud y i 6
ASTRONOMY DID YOU KNOW ight takes about eight minutes to les from the Sunl l l travel the 93 mi Sun to the Earth ion mi Look at the sky What do you see If it’s day you’ll see the Sun If it’s night you’ll see the Moon And if the sky is clear you’ll see stars In big cities you may see only a few hundred stars But out in the country or on the ocean you’ll see many thousands You may even see planets and if you’re lucky a comet There are people who look at the sky for hours and hours night after night They study the stars the planets and other objects in the sky These people are called astronomers The word astronomy comes from the Greek for star and arrangement Astronomers study the universe in many different ways Some watch faraway objects Others work in laboratories where they look at samples of meteorites rocks from the Moon and space debris from other planets Some try to make models of different objects people have studied Not all astronomers get paid for the work they do Some do it for a hobby Such people are called amateur astronomers How do astronomers study objects that are millions even billions of miles away They use powerful telescopes that make things look large enough to be seen in detail Some telescopes are small enough to be held in the hand Others are as big as a school bus LEARN MORE READ THESE ARTICLES COPERNICUS SOLAR SYSTEM UNIVERSE Answer They study all of these except for astronauts 7
