HowStuffWorks "How the Moon Works"
[http://www.howstuffworks.com/] SUBSCRIBE Adventure Animals Auto Culture Entertainment Health Home & Garden Lifestyle Money Science Tech Video Shows Quizzes Engineering Environmental Science Forces of Nature Innovation Life Science Military Physical Science Dictionary Science Vs. Myth Space Transportation Home / Science / Space / Astronomy / The Solar System More Stuff Like This 10 Scientific Words You're Probably Using Wrong 10 False Science Facts Everyone Knows Puzzle: Nerve Cell How the Moon Works by Craig Freudenrich, Ph.D. Page 1 Introduction to How the Moon Works 2 What's on the surface of the moon? 3 Giant Impactor Hypothesis 4 Geologic History of the Moon Moon Image Gallery Looking at the full moon, you can clearly see dark areas (maria) and light ones (terrae). See more moon images . NASA/Photodisc/ Getty Images Up Next How the Earth Works How the Sun Works From anyplace on Earth , the clearest thing in the night sky is usually the moon, Earth's only natural satellite and the nearest celestial object (240,250 miles or 384,400 km away). Ancient cultures revered the moon. It represented gods and goddesses in various mythologies -- the ancient Greeks called it "Artemis" and "Selene," while the Romans referred to it as "Luna." When early astronomers looked at the moon, they saw dark spots that they believed were seas ( maria ) and lighter regions that they believed was land ( terrae ). Aristotle's view, which was the accepted theory at the time, was that the moon was a perfect sphere and that the Earth was the center of the universe. When Galileo looked at the moon with a telescope , he saw a different image -- a rugged terrain of mountains and craters. He saw how its appearance changed during the month and how the mountains cast shadows that allowed him to calculate their height. Galileo concluded that the moon was much like Earth in that it had mountains, valleys and plains. His observations ultimately contributed to the rejection of Aristotle's ideas and the Earth-centered universe model. Because the moon is so close to the Earth relative to other celestial objects, it's the only one to which humans have traveled and set foot upon. In the 1960s, the United States and Russia were involved in a massive "space race" to land men on the moon. Both countries sent unmanned probes to orbit the moon, photograph it and land on the surface. In July 1969, American astronauts Neil Armstrong and Edwin "Buzz" Aldrin became the first humans to walk on the moon. During six lunar landing missions from 1969 to 1972, a total of 12 American astronauts explored the lunar surface. They made observations, took photographs , set up scientific instruments and brought back 842 pounds (382 kilograms) of moon rocks and dust samples. What did we learn about the moon from these historic journeys? Let's take a closer look at the moon. We'll examine its surface features and learn about its geology, internal structure, phases, formation and influence on the Earth. Print Cite This! Close Please copy/paste the following text to properly cite this HowStuffWorks article: Freudenrich, Ph.D., Craig. "How the Moon Works" 06 March 2008. HowStuffWorks.com.
14 August 2014. Citation & Date Feedback Page 1 Introduction to How the Moon Works 2 What's on the surface of the moon? 3 Giant Impactor Hypothesis 4 Geologic History of the Moon 5 Moon Phases 6 Return to the Moon 7 Lots More Information More To Explore All Things Science 10 Incredible Wind Power Facts 10 Remarkable Exoplanets Fact or Fiction: Earthquakes Top 10 Things That Women Invented Strange, Spooky, Scary: The Supernatural Quiz Watch 100 Greatest Discoveries videos » You Might Also Like How the Moon Works The moon is often the largest object in the sky outside of the sun. What is the moon made of, how did it form -- and why do people blame it for their strange behavior? How Stars Work When you look up at night and see thousands of stars, have you ever wondered what you are looking at? Learn what stars are and how they live and die! Popular Articles Could we stop an asteroid on a collision course toward Earth? Cancer Aquila Most Popular Most Watched Most Popular 10 Reasons Why Tesla Is a Scientific God Strange, Spooky, Scary: The Supernatural Quiz 10 Heaviest Objects Mankind Has Ever Moved How Hydraulic Machines Work 10 Correlations That Are Not Causations Most Watched How to Make (Almost) Everything Understanding Bridges How do they do it? Why aren't the keys on my computer in alphabetical order? The Most Important Things So Far, Seriously Don't Miss Stuff You Should Know: Demystifying Your World Stuff Mom Never Told You: All Things Women and Gender Stuff You Missed in History Class: Fact or Fiction? CHECK OUT OUR PODCASTS HOWSTUFFWORKS NEWSLETTER THE LATEST AND GREATEST SUBSCRIBE HOWSTUFFWORKS Adventure Animals Auto Culture Entertainment Health Home & Garden Lifestyle Money Science Tech MORE STUFF Blogs HSW Tools RSS Maps Podcasts Quizzes Newsletters Video HSW Brazil HSW China STUFF WEBSITES BrainStuff CarStuff Fw:Thinking Stuff Mom Never Told You Stuff of Genius Stuff They Don't Want You to Know Stuff to Blow Your Mind Stuff You Missed in History Class Stuff You Should Know CUSTOMER SERVICE Advertising Contact Us Help CORPORATE About Us Careers @ HSW Privacy Policy Visitor Agreement TAKE US WITH YOU FOLLOW US Copyright © 1998-2014 HowStuffWorks, a division of InfoSpace LLC