earths moon

Earth’s Moon

Earth Science

1st Semester

• Most of the knowledge about the Moon comes from the Apollo Missions conducted by the Unites States between the years 1969 and 1972.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

• Some information that has been determined at this point is that the Moon has a density of 3.3 g/mL, while the Earth has a density of 5.5g/mL

• The difference is due to the Moon having a small iron core.

• As a result of its small mass the Moon has 1/16th the gravity of the Earth.

The Lunar Surface

• The moon has no liquid water on its surface nor any form of an atmosphere.

• As a result, the Moon’s surface cannot be worn down by the action of moving wind and water, a process called weathering and erosion on Earth.



• The Moon is not tectonically active right now, so volcanic eruptions do not occur any longer



• Since the Moon has no atmosphere, particles from space continually bombard its surface, gradually smoothing out the landscape.

Craters

• The term used to describe round depressions in the surface of the moon.

• There are many, the largest being the width of the state of Indiana.



• Craters are caused by the impact of rapidly moving meteoroids.

• Meteoroids are small solid particles of rock or metal that travel through space.



• In contrast to the Moon, the Earth has very few recognizable craters on its surface. QuickTime™ and a

TIFF (Uncompressed) decompressorare needed to see this picture.

• When meteoroids come through Earth’s atmosphere, the friction that is caused tends to burn most of them up.



• The ones that do make it leave little evidence for us to examine today, as the forces of erosion, and plate movement have erased most of the craters.



Formation of a Crater

• When a meteoroid strikes the surface of the moon, it will compress the material that it strikes.



• There will be some rebound, where material is thrown back up from the new crater.



• Most of this ejected material will land near the crater and build a rim around it.

• The heat generated by the impact is enough to melt rock into molten glass.



• The larger craters on the Moon, like Kepler and Copernicus, are believed to be relatively young because of the bright rays or splash marks that radiate out form the crater.

Highlands

• This moon landscape feature makes up most of the lunar surface.

• These densely pitted, light colored areas contain mountain ranges whose peaks reach as high as the Himalayas on Earth.



Mare

• The term given to any dark, relatively smooth area on the moon’s surface. If there is more than one, they are called maria.



• They were thought to have originated when asteroids were able to puncture the lunar surface, releasing magma from the interior.



• Asteroids are relatively small, rocky bodies with a size from a few hundred kilometers to less than a kilometer.



• Scientists have determined that the maria are comprised of a type of hardened lava known as basalt.



• Scientists theorize that the material that fills the maria could be thousands of kilometers thick.QuickTime™ and a


• A surface feature known as a rille is associated with maria.

• Rilles look very much like valleys or trenches.

• Scientists think they may be the remnants of ancient lava flows.



Regolith

• Any lunar terrain will be covered with a layer of grey debris from the millennia of bombardment from meteorites.

• This soil like layer is called a lunar regolith.



• It is composed of volcanic rocks, bead like glass, and really fine lunar dust. QuickTime™ and a


• In portions of the Moon explored by astronauts, the lunar regolith was over three meters thick.QuickTime™ and a


earths moon

Technology

lunar surface

surface feature

moons surface

moon landscape feature

earths moon earth science

moon hasno liquid wateron

moon has116 ththe gravity

lunar terrain