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- 1. Earths Moon Earth Science 1st Semester
- Most of the knowledge about the Moon comes from theApollo Missionsconducted by the Unites States between the years1969 and 1972 .
- Some information that has been determined at this point is that the Moon has a density of3.3 g/mL , while the Earth has a density of5.5g/mL
- The difference is due to the Moon having asmall iron core.
- As a result of its small mass the Moon has1/16 ththe gravity of the Earth.
4. 5. The Lunar Surface
- The moon hasno liquid wateron its surface nor any form of anatmosphere .
- As a result, the Moons surface cannot be worn down by the action of moving wind and water, a process calledweathering and erosionon Earth.
- The Moon is nottectonicallyactive right now, sovolcanic eruptionsdo not occur any longer
- Since the Moon has no atmosphere, particles from space continually bombard its surface, graduallysmoothing out the landscape .
- The term used to describeround 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 ofrapidly moving meteoroids .
- Meteoroids aresmall solid particles of rock or metalthat travel through space.
- In contrast to the Moon, the Earth hasvery fewrecognizable craters on its surface.
- When meteoroids come through Earthsatmosphere , the friction that is caused tends toburnmost of them up.
- The ones that do make it leave little evidence for us to examine today, as the forces oferosion, and plate movementhave erased most of the craters.
15. Formation of a Crater
- When ameteoroidstrikes the surface of the moon, it willcompressthe material that it strikes.
- There will be somerebound , where material is thrown back up from the new crater.
- Most of this ejected material will land near the crater and build arim around it .
- Theheatgenerated by the impact is enough to melt rock intomolten glass .
- Thelargercraters on the Moon, like Kepler and Copernicus, are believed to berelatively youngbecause of the brightrays or splash marksthat radiate out form the crater.
19. 20. Highlands
- This moon landscape feature makes upmost of the lunar surface .
- Thesedensely pitted, light colored areascontainmountain rangeswhose peaks reach as high as the Himalayas on Earth.
21. 22. Mare
- The term given to anydark, relatively smootharea on the moons surface.If there is more than one, they are calledmaria .
- They were thought to have originated whenasteroidswere able to puncture the lunar surface, releasingmagmafrom the interior.
- Asteroidsare 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 ofhardened lavaknown asbasalt .
- Scientists theorize that the material that fills the maria could bethousands of kilometers thick.
- A surface feature known as arilleis associated with maria.
- Rilles look very much likevalleys or trenches .
- Scientists think they may be the remnants ofancient lava flows.
- Any lunar terrain will be covered with alayer of grey debrisfrom the millennia of bombardment from meteorites.
- This soil like layer is called alunar regolith .
- It is composed ofvolcanic rocks, bead like glass, and really fine lunar dust .
- In portions of the Moon explored by astronauts, the lunar regolith was overthree meters thick.