The Solar System
What are the two
general category types
for planets in our solar
system?
Terrestrial Planets
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Made of dense rock material
Smaller planets
Inner planets
Thin atmosphere
Jovian Planets
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Made of less dense gasses
Larger planets
Outer planets
Thick atmosphere
Describe the
characteristics of each.
In the spaces below, describe a few characteristics about each of the bodies in our solar system
The Sun
Huge Fusion Reactor: Is slowly loosing mass through the fusion process
(E = mc2). Will run out of fusionable material in about 5 billion years.
Mercury
The Fast Planet: named after the messenger to the Roman gods
Venus
Earth’s Sister Planet: Brightest object in the night sky besides the moon
Earth
The Blue planet: Only Planet in or solar system known to sustain life.
Mars
The Red Planet: Named after the Roman god of war
Jupiter
The Largest Planet: Named after the Roman “King of all gods” because it
is the brightest object that is visible all night
Saturn
The Elegant Planet: Least dense of all planets 0.7g/ml
Uranus
The Sideways Planet: Rotates on its side
Neptune
The Windy Planet: Named after the Roman God of the oceans.
Pluto
Smallest of the 9: No longer considered a planet. Downgraded to “dwarf
planet” in August 2006.
What is required to
qualify a celestial body
as a planet?
Why isn’t Pluto
considered to be a planet?
It must be in orbit around the Sun
It must be large enough that it takes on a nearly round shape
It has cleared its orbit of other objects
Pluto was automatically disqualified because its highly elliptical orbit
overlaps with that of Neptune.
Planets: The eight worlds from Mercury to Neptune.
List and describe the
three classifications of
bodies in our solar
system.
Dwarf Planets: Pluto and any other round object that "has not cleared the
neighborhood around its orbit, and is not a satellite."
Small Solar System Bodies: All other objects orbiting the Sun.
With all of the recent space exploration and new discoveries, is it likely that we will discover and
new significant bodies in or solar system?
Summary
The Moon
Describe the density and
Density and composition is comparable to that of the Earth’s mantel.
composition of the Moon. The relative mass is less due to the smaller size of iron core.
Craters
Describe the three major
features of the moon
Most obvious feature.
Formed by meteor impacts
Seen as brighter regions on the surface of the moon.
Highlands
Densely pockmarked areas that make up the majority of the moon’s
surface.
Created by multiple crater hits
Maria
Compare the surface of
the far side of the Moon
to the near side.
What would account for
this difference?
Darkened basin areas.
Created basalt flows from under the surface of the moon
The near side shows far less of the pockmarked system of highlands
whereas the far side is primarily highlands
The most likely reason for this difference is that the Earth forms a type of
shield that protects the near side from as many meteor hits as the far side.
The Moon is exposed to the same amount of meteor debris as the Earth is. Why then does the
Earth not show the craters as obviously as the Moon does? (Two reasons)
Summary
Reason One: The majority of the would-be meteors that could strike the Earth are burned up
in the Earth’s atmosphere. The Moon has no atmosphere so it has less protection
Reason Two: The Earth has many erosional processes (weathering & plate tectonics) that
slowly remove the evidence of a meteor impact. The moon does not have these processes and
therefore the craters remain for 100’s of thousands of years.