Ch 21: Mercury

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Ch 21 Mercury
epod.usra.edu
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• I. Mercury
• A. Motion
• 1. orbits sun in 88 days, orbit is very
  elliptical
• 2. Rotation takes 58.5 days!
• 3. each time is orbits the sun, it rotate 1.5x
  
• (rotates 3 x for every 2 orbits)
• 4. can be seen from earth at sunrise or sunset
  b/c it is so close to the sun
• 5. suns gravity causes tides on the crust of
  the entire planet (no oceans)

www.crystalinks.com
zebu.uoregon.edu
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I. Mercury A. Motion 1. orbits
sun in 88 days, orbit is very elliptical
2. rotates in 58.5 days! 3. can be
seen from earth at sunrise or sunset b/c it is
so close to the sun 4. suns
gravity causes tides on the entire planet (no
oceans)
www.kidzworld.com/.../article/a354i0_185.gif

• B. Surface
• 1. 1/3 size of earth
• 2. temp. at surface 700 to 100K (427 ºC to
  -173 ºC)
• 3. Topography moon like
• a. Craters up to 1300 km in diam.
• b. Lobate scarps great curved cliffs (due
  to shrinkage) up to 3 km tall
• c. Plains
• d. Minor erosion from micrometeorites

www.nasm.si.edu
science.nasa.gov
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B. Surface 1. 1/3 size of earth 2.
temp. at surface 700-100K (427 C to -173C)
3. Topography a. Craters up to 1300 km in
diam. b. Lobate scarps curved cliff
(shrinkage) c. Mountains 3 km high d.
Plains e. No erosion dead planet

• C. Atmosphere
• 1. airless too small, not enough gravity to
  hold an atmosphere
• D. Interior
• 1. denser than the moon, but surface is rock
  (low density
• 2. Therefore, there must be a large core of
  dense materials such as iron
• 3. has a small magnetic field
• 4. inactive

en.wikipedia.org
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Mariner 10

• measured Mercury's environment, atmosphere,
  surface, and body characteristics and on the
  way made similar investigations of Venus in the
  1970s
• Flew by Mercury 3 times
• Took 2800 photos
• Mapped 40-50 of the surface

http//messenger.jhuapl.edu/index.php
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Messenger

• Launched in 2004
• Will be first to orbit mercury
• Has flown by two times

http//messenger.jhuapl.edu/index.php