|
1
|
- Earth and The Terrestrial Worlds
|
|
2
|
- Comparative Planetology is the study of the solar system through
examining and understanding the similarities and differences among the
planets.
- Planetary Geology:
- The study of surface features and the processes that create them is
called geology.
- Today, we speak of planetary geology, the extension of geology to
include all the solid bodies in the solar system.
|
|
3
|
- Spacecraft have visited and photographed all of the terrestrial worlds.
Some have even been landed on!
- Because surface geology depends largely on a planet’s interior, we must first
look inside the terrestrial worlds.
|
|
4
|
|
|
5
|
- Surface Views of some of the terrestrial worlds.
- Venus, the Moon and Mars have all been landed on successfully by spacecraft from Earth.
|
|
6
|
- When subjected to sustained stress over millions to billions of years,
rocky material slowly deforms and flows.
- Rock acts more like Silly PuddyTM , which stretches when you
pull it slowly but breaks if you pull it sharply.
- The rocky terrestrial worlds became spherical because of rock’s ability
to flow.
- When objects exceed about 500 km
in diameter, gravity can overcome
the strength of solid rock
and make a world spherical
|
|
7
|
- Gravity also gives the terrestrial worlds similar internal structures.
- Distinct layers are formed by differentiation.
- Differentiation is the process by which gravity separates materials
according to their density.
- This resulted in three layers of differing composition within each
terrestrial planet.
- Core
- Mantle
- Crust
|
|
8
|
- Lithosphere: Outer layer of relatively rigid rock that encompasses the
crust and the uppermost mantle.
|
|
9
|
- Heat flows from the hot interior to the cool exterior by conduction and
convection.
- Condution: Heat transfer as a result of direct contact.
- Convection: Heat transfer by means of
hot material expanding and rising and cool material contracting
and sinking.
- A small region of rising and falling material is called a convection
cell.
|
|
10
|
- Impact Cratering: the excavation of bowl-shaped depressions (impact
craters) by asteroids or comets striking a planet’s surface.
- Volcanism: the eruption of molten rock, or lava, from a planet’s
interior onto it’s surface.
- Tectonics: the disruption of a planet’s surface by internal stresses.
- Erosion: the wearing down or building up of geological features by wind,
water, ice, and other phenomena of planetary weather.
|
|
11
|
|
|
12
|
|
|
13
|
|
|
14
|
- c) “Sticky” lava makes steep-sloped stratovolcanoes.
|
|
15
|
|
|
16
|
|
|
17
|
|
|
18
|
|
|
19
|
|
|
20
|
- The Troposphere becomes warmer
than it would if it had no greenhouse gases.
- Greenhouse gases include:
|
|
21
|
|
|
22
|
|
|
23
|
- Ultraviolet light is absorbed in the Stratosphere.
- X-Rays are absorbed in the Thermosphere and Exosphere.
|
|
24
|
- The Magnetosphere blocks the Solar Wind
- This produces two regions where the charged particles get trapped – Van
Allen Belts.
|
|
25
|
|
|
26
|
- The interaction of the charged particles from the solar wind near the
poles, produces the:
- Aurora Borealis (Northern Lights)
- Aurora Australis (Southern Lights)
|
|
27
|
|
|
28
|
- Outgassing from Volcanic activity was most responsible for producing the
earth’s early atmosphere. (Volcanoes give off H2O, CO2,
N2, and sulfur compounds.
- As life developed, it too influenced the atmosphere of the Earth,
allowing it to become what it is today. (e.g. plants give off O2 and
consume CO2)
|
|
29
|
|
|
30
|
|
|
31
|
|
|
32
|
|
|
33
|
|
|
34
|
|
|
35
|
|
|
36
|
|
|
37
|
|
|
38
|
|
|
39
|
|
Notes
