Transcript The Moon - Mid-Pacific Institute

The Moon
Joel Tome
Aaron Fujioka
Pd. 3
The Moon
• A roughly spherical and rocky
body which orbits the Earth at an
average distance of 382,942 km
• Moon diameter = ¼ Earth
diameter
• Moon mass = 1/80 Earth mass
Rotation and Orbit
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Rotates on axis every 29.5 days
Axis tilted
Craters near south pole always in shadows
Sidereal month: complete orbit of Earth
Synodic month: one lunar day, relative to sun
Origin and Evolution
• Collision known as “Giant Impact” or the “Big
Whack”
• Occurred 4.6 billion years ago between Earth
and planet-sized object
• Resulted in a cloud of vaporized rock which
came from Earth’s surface
Origin and Evolution cont.
• Vaporized rock went into Earth’s orbit
• Cloud cooled and condensed into a ring of
small and solid bodies
• Gathered together and formed the moon
Origin and Evolution cont.
• The quick joining together released lots of
energy as heat
• Creating an “ocean” of magma
• It slowly cooled and solidified
Origin and Evolution cont.
• As the crust formed, asteroids continually hit
the moon
• One created the South Pole-Aitken Basin
• One of the largest known impact craters in
solar system
Interior of the Moon
• Crust- Average thickness is 43 miles
• Mantle- Formed during period of global
melting, low density minerals floated to the
outer layers and dense minerals sank deeper
• Core- Radius of 250 miles, consists mostly of
iron and may contain large amounts of sulfur
Surface Features
• Craters: result from meteoroids, asteroids, comets
• Basins: craters 190 mi or more in diameter, rings
vary with size
• Maria: dark areas on the surface of the moon
(16% of SA)
Surface Features cont.
• Wrinkle ridges: blister-like humps across Maria
• Rilies: snakelike depression across Maria
• Volcanic features: dome/cone-shaped areas
The moon’s volcanic past
• Contained active volcanoes for billions of
years
• Large dark areas filling the moon’s craters
indicate the largest volcanic flows
• Almost exclusively on the near side
Works Cited
• Angelo, Joseph A., Jr. "Moon." Science Online. Facts On File, Inc. Web. 21
Jan. 2011.
<http://www.fofweb.com/activelink2.asp?ItemID=WE40&SID=5&iPin=ESA
1805&SingleRecord=True>.
• Elkins-Tanton, Linda T. "Moon." Science Online. Facts On File, Inc. Web. 18
Jan. 2011.
<http://www.fofweb.com/activelink2.asp?ItemID=WE40&SID=5&iPin=SSE
M0007&SingleRecord=True>.
• "Moon." Gale Encyclopedia of Science. Ed. K. Lee Lerner and Brenda
Wilmoth Lerner. 4th ed. Detroit: Gale Group, 2008. Discovering Collection.
Gale. Mid-Pacific Institute. 14 Jan. 2011
<http://find.galegroup.com/srcx/infomark.do?&contentSet=GSRC&type=r
etrieve&tabID=T001&prodId=DC&docId=EJ2644041517&source=gale&src
prod=DISC&userGroupName=mid&version=1.0>.
• Spudis, Paul D. "Moon." World Book Advanced. World Book, 2011.
Web. 18 Jan. 2011.