4 YouTube - How the Moon was born! ORIGIN OF THE MOONSCIENTIST BELIEVE THE MOON FORMED WHEN A LARGE OBJECT ABOUT THE SIZE OF A PLANET HIT EARTHYouTube - How the Moon was born!
5 DEVELOPMENT OF THE MOON SURFACE LAYERS MELTED BY FREQUENT IMPACTS AND CREATED CRATERSFORMED MAGMA OCEANLIGHTER MATERIALS ROSE TO SURFACE – COOLED AND HARDENED4.0 – 3.5 BILLION YEARS AGO IMPACTS DECREASEDOVER MILLIONS OF YEARS MAGMA RICH IN IRON ERUPTED FILLING LARGE BASINS CREATING MARIA
6 MOON TODAY CORE INACTIVE IMPACTS FROM MICROMETEOROIDS CONTINUE TO CHANGE SURFACE THROUGH IMPACTS AND EROSIONMOON HAS NO ATMOSPHERE TO BURN THEM UP
7 PROPERTIES AND FEATURES OF THE MOON Same side of moon faces earth – geosynchronous orbitAbout 384,000 km (240,000 miles) from Earth3,476 km (2,155 miles) in diameter (about ¼ the size of Earth)Density 3.3g/cm31/6 Earth’s gravity
8 Far Side of the Moon First seen by Luna 3 Russian space probe in 1959 Surface features different from near sideMore cratersVery few mariaThicker crust
9 Layers of the moon Mantle Near side crust (about 65 km thick) Far side crust (about 150km thick)Iron Core
10 The Moon’s Surface No atmosphere No liquid water Extreme temperatures Daytime = 130C (265°F)Nighttime = -190C (-310 F
11 Maria Originally thought to be “seas” by early astronomers Formed from lava coming up through cracksDarkest parts of lunar landscapeMostly basalt rock made of feldspars, pyroxene, youngest rocks
15 Highlands Mountains up to 7500 m (25,000 ft) tall Thought to be original crustFormed from impactsLighter in color than mariaRocks samples similar to Gabbro and Breccia – rocks made of angular fragments – impacts melted rocks together
22 Explanation: When a meteorite strikes the Moon, the energy of the impact melts some of the splattering rock, a fraction of which might cool into tiny glass beads. Many of these glass beads were present in lunar soil samples returned to Earth by the Apollo missions. Pictured above is one such glass spherule that measures only a quarter of a millimeter across. This spherule is particularly interesting because it has been victim to an even smaller impact. A miniature crater is visible on the upper left, surrounded by a fragmented area caused by the shockwaves of the small impact. By dating many of these impacts, astronomers can estimate the history of cratering on our Moon.