Download Planets: Comparing their structure

Planets:
Comparing
their structure
Earth Science
Objectives
To compare and contrast Terrestrial and
Jovian planets in terms of:
Formation temperature
What types of materials they are made of
(solids, liquids, or gases)
Size
Location in the solar system
All 8 Planets must:
• Have an elliptical orbit
around the Sun
• Are spherical in shape
• Have completed
accretion
•“cleared their
neighborhood”
•No more dirty rings
What about Pluto?
When Pluto was
discovered in the
1940s, it was the
largest thing in its
orbit.
With better
equipment, we now
know that it is one of
hundreds of things in Because Pluto is not accreting,
the Kuiper belt
or cleaning up it’s neighborhood,
it is classified as a Dwarf Planet.
What about Pluto?
When Pluto was
discovered in the
1940s, it was the
largest thing in its orbit.
We didn’t see anything
else there.
With better equipment,
we now can see that it
still travels through a
part of a “dirty ring”
called the Kuniper belt
Because Pluto has not
completed accretion, it is now
classified as a Dwarf Planet.
Planets
Our 8 planets can be divided into two major groups
based on their size, location in the solar system, &
what they are made of:
Terrestrial Planets: the 4 planets closest to
the sun.
sun They are small and made of solids,
like rocks.
rocks
Jovian planets: the 4 planets that are the
farthest from the sun.
sun They are large gas
giants,
giants all have rings (Jupiter is the dimmest,
Neptune the brightest)
The two types of planets are separated by the
asteroid belt
MVEM and JSUN
Terrestrial
Planets
Jovian
Planets
Terrestrial vs. Jovian
Group
Distance
Temp for
from
formation
sun
High
Terrestrial
M,V,E,M
Close
(forms at
high temp)
Jovian:
J,S,U,N
(jason)
Far
Low
(forms at
cold temp)
Type of
Material
Size
Solid
Small
Gas
Large
Why…
Why do terrestrial planets form at high
temperatures?
Because they are closest to the sun, they form at
higher temperatures.
Why are terrestrial planets smaller than jovian
planets?
1. As the gas changes into a liquid and eventually
into a solid, it shrinks!
2. Terrestrial planets are smaller because the sun
took so much of the dust and gas around it,
leaving little to form the Terrestrial planets.
Why?
Why are jovian planets larger?
1. Jovian planets are so far away from the
sun that there was a lot more dust and gas
available to accrete and form the planet.
2. Jovian planets are made of gases, mostly
hydrogen and helium gas. Gases expand
to fill the available space.
Scale of Planets
It would take 1 million
Earths to be the same
size as the sun.
The distance from the
Earth to the sun is called
1 AU or astronomical
unit.
This is equal to 0.000158
light years. It takes
0.00158 years for light to
travel from the Sun to
Earth
00
0
,
0
0
U
0
X 11, A
Terrestrial Planets:
Mercury
Closest to the sun
Barely bigger than the
Earth’s moon
Moon like surface with
craters
Greatest temperature
extremes
From -100 to 400 degrees
Celsius
Terrestrial Planets:
Venus
The “Veiled planet”
Atmosphere like Earth’s
97% of atmosphere is CO2 so
light can’t get through
Extreme levels of volcanoes
and tectonic activity
Hot gassy atmosphere
Very high temperatures
(~900 ºF)
Trapped gases can’t get out!
US & Russian probes
Increased heat due to
have landed on Venus
Greenhouse effect
Terrestrial Planets:
Earth
Our home
Is defined to be 1
Astronomical Unit
(AU) from the sun
We will learn in great
detailH later
1 AU
Terrestrial Planets:
Mars
The “red planet”
Has massive dust
storms on its surface
Has water
Very oldH the highly
cratered southern
hemisphere is 3.5 to 4.5
billion years old!
Jovian Planets:
Jupiter
The largest planet
Is 2 ½ times larger
than all the other
planets combined!
Atmosphere is made
of Hydrogen & Helium
Has convection
currents like the sun
from internal heat that
produces colored
bands.
Jovian Planets:
Saturn
Rings !
Has the lowest
density of any
planet
Surrounded by
“moonlets”
Surface winds up to
1600 feet/sec
Jovian Planets:
Uranius
The sideways planet
It rotates parallel to its
orbital plane.
plane
Jovian Planets:
Neptune
Has the “Great Dark
Spot”
Large Storm that is the
size of the entire Earth
Winds up to 1600 mi/hr
Planetary Data