 The only natural satellite of our planet is the moon, named “The Moon”  Some publications will refer to it as “Luna”

 For our solar system the planet-satellite relationship between Earth and the Moon is unusual  The Moon is unusually large compared to Earth  It’s diameter is 3,475 kilometers, about ¼ the size of Earth (12,756 kilometers)  This makes the moon the 5 th largest satellite in our solar system

 From calculation of the Moon’s mass, we know that its density is 3.3 times that of water (Earth’s is 5.5 times that of water)  The moon has approximately 1/8 the mass of Earth  The moon is approximately ¼ the size of Earth  Gravitational attraction at the lunar surface is 1/6 of that experienced on Earth’s surface  If you weighed 180 lbs. on Earth you would only weigh 30 lbs. on the Moon  During missions to the moon, astronauts could jump six times higher than they could on Earth because of the lower gravity

 There are 3 major features on the Moon  Maria, Highlands, and craters are the major features  The moon doesn’t have liquid water or an atmosphere  Without either, the kind of erosion and weathering we have on Earth doesn’t occur  Since the Moon doesn’t have an atmosphere it is subjected to a different type of erosion  Debris (tiny rocks/particles) from space continually fly into the surface and gradually smooth out the landscape

 Most noticeable feature on the surface of the moon are craters  Craters are depressions that are created by a meteorite impacts  Many craters on the moon  Largest are about 250 kilometers in diameter  This is roughly the width of the state of Indiana  Earth has some crater impacts, but many of them have been eroded/weathered away

As an object flies into the surface of the moon it will act almost like a rock being thrown into a body of water. The force will drive downwards and outwards. Material will fly up into the air just like water splashes. The end result will be a depression left on the surface. Crater Impact Video

 Most of the surface of the moon is made up of densely pitted, light-colored areas known as highlands  Within the highland areas are mountain ranges  Highest peak is almost 8 km, which is only 1 km lower than Mount Everest

 Mare (maria: plural) is the dark, relatively smooth area on the moon’s surface  These originated when asteroids/meteorites struck the lunar surface which let magma leak out onto the surface  Rilles are long channels that look similar to valleys or trenches  Geologists believe they may be the remnants of ancient lava flows

 Lunar Regolith is the soil-like layer that is composed of igneous rock, glass beads, and fine lunar dust  Apollo astronauts studied regolith on lunar missions and found that it is just over 3 meters thick

 Even though astronauts have walked on the lunar surface, little is still known about the origin of our nearest neighbor  The most widely accepted hypothesis/theory for the origin of the moon is that during the early formation of our solar system an object roughly the size of Mars impacted Earth  This impact would have ejected large quantities of crustal and mantle rock from our planet and some of this would have been caught into our orbit and formed into the Moon

 The ejected material would have been mostly iron-poor mantle and crustal rocks  This information accounts for the lack of a sizable iron core on the moon  The material would have remained in orbit long enough that any water from Earth would have been lost

 The content for this presentation came from the Prentice-Hall Earth Science textbook  Pictures/animations came from websites on the internet