TABLE OF CONTENTS Eyes to the Skies 4 Watching Gravity Keeping Time 10 The Curious Case of Pluto 20 Mind-Blowing Math and Freaky Physics 26. Citizen Scientist 37 Timeline 45 Glossary 46. Index 47 Show What You Know 47 Websites to Visit 47 About the Author 48
EYES TO THE SKIES As long as people have been on Earth they have stared with wild wonder into the night sky What is out there Why are the stars twinkling How far away is the Moon Human understanding of the Moon stars and worlds beyond our own has grown by leaps and bounds over just the past few generations Stars are so far from Earth that their light is distorted by Earth’s atmosphere and they sometimes appear to twinkle Visible planets such as Venus do not twinkle because they are much closer 4
FIELD NOTES Most astronomers concentrate on a particular question or area of astronomy planetary science solar astronomy the origin or evolution of stars or the formation of galaxies Observational astronomers spend their time designing and carrying out observational programs with a telescope to answer a question or test the predictions of theories 5
