The Moon Formation EarthMoon System Earths Moon 3475

The Moon Formation & Earth-Moon System

Earth's Moon • • 3475 kilometers (2150 miles) in diameter Similar to Earth's crustal rocks Gravitational attraction is one-sixth of Earth's No atmosphere

Earth's Moon

Lunar Surface • Maria (mare sing. ) Latin for sea • Dark regions – solidified lava flows • Lowlands with fewer craters

Lunar Surface • Highlands • Bright areas, many craters • Make up all of the "back" side of the Moon • Older than maria

Lunar History • The impact theory of the moon's formation • Earth's moon formed from a collision between the early Earth and a Mars-sized object. • http: //www. classzone. com/books/earth_science/terc/content/visualizations/es 2501 page 01. cfm? chapter_no=visualization

Phases of the Moon • The Moon orbits Earth in a counter-clockwise direction • The positions of the Sun, Earth & Moon are constantly changing • Lunar phases result from the motion of the Moon and the sunlight that is reflected from its surface.

Phases of the Moon

Phases of the Moon Click on the picture to begin the animation. Click again to pause.

Phases of the Moon • Check out this page for definitions of each of the different lunar phases. – http: //aa. usno. navy. mil/faq/docs/moon_phases. php • Be sure to watch the Lunation movie at the bottom of the page.

Phases of the Moon • How long does it take for the Moon to complete one revolution around the Earth? • 27 days

Phases of the Moon • Why do you see the same side of the moon? • The Moon’s period of rotation = it’s period of revolution (27 days) • The same lunar hemisphere always faces Earth