1. EARTH’S MOON

2.  Structure  3,476 km in diameter  1/18 the mass of the Earth  No air or liquid water  Temperature range: 100◦C to -120◦C (212◦F to -184◦F)  1/6 of Earths gravity

3.  Origin of the Moon  Evidence of the origin is called collision theory  Object as large as Mars collided with Earth  Material from the object and Earth’s outer layers were thrown into orbit

4.  Surface  Craters  Caused by the impacts of meteoroids  Thousands of miles in diameter  Highlands  Mountain like areas  Maria- Latin for sea  Dark, flat surfaces on surface  Galileo thought they were oceans  Low, dry areas that were flooded with molten material, billions of years ago

5.  Moon rocks and Moonquake  Rocks were formed from the cooling of molten material  What scientists know about the moon has mostly came from the moon rocks collected by astronauts  Moonquakes happen because the of changes deep under the moon’s surface

6.  Missions  Surveyor spacecraft showed that the moon was solid  July 20, 1969, Apollo 11-Lunar Module Eagle  First man on the moon-Neil Armstrong  Gathered rocks and surface samples  Photographs show minerals and map the entire surface of the moon