Transcript Satellites of Other Planets

Satellites of Other Planets
Section 3
Pg 733-744
Mars’ Moons
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Phobos and Deimos
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Fear and Terror
Potato shaped
captured asteroids
Moons of Jupiter
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Galileo
observed 4
moons orbiting
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Now we have
observed dozens
Largest 4 known
as Galilean
moons
Galilean Moons
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Io
Europa
Ganymede
Callisto
Io
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Active volcanoes
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Io moves inward and
outward in orbit and
experiences gravitational
pull from other moons
This causes the surface
to move in and out by
100 m.
Heat from the friction
from surface flexing
causes volcanoes
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Europa
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metallic core, an
extensive rocky mantle
smooth shell of ice, and it
is often speculated –
though far from proven –
that a global ocean of
liquid water is concealed
underneath
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most likely haven of
extraterrestrial life
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If the moon's interior is
warm enough to sustain
an ocean, and if the ice
crust is thin enough to
permit the passage of
sunlight, then perhaps
aquatic organisms have
evolved
Ganymede
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Larger than Mercury
Plate tectonics
Magnetic field
Callisto
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No internal layers
geologically dead
craters
Moons of Saturn
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At least 47
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Titan the largest
Uranus and Neptune have moons
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Uranus two dozen
moons
Neptune 13 moons
Pluto
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Although no longer
considered a planet
Pluto has three small
moons
Charon is almost half
the size of Pluto they
share a barycenter
Rings of Gas Giants
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We usually think of
Saturn, but other
planets have rings too
Pieces range in size
from particles the size
of dust to chunks the
size of a house
Asteroids, Comets and
Meteoroids
Other stuff out there
Asteroids
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Fragments of rock
that orbit the sun
More than 50,000
Largest is Ceres
Most are in the
asteroid belt located
between Mars and
Jupiter
Other Asteroid Locations
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Trojan asteroids
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Concentrated in
groups ahead of
and behind
Jupiter
Near Earth Asteroids
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Have wide, elliptical
orbits that bring them
close to Earth
Small percentage
Can cause major
damage
Now we ID and
monitor to hope to
predict and possibly
avoid future collisions
Russian: Meteor or Meteorite?
Chelyabinsk
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Meteor exploded in
the air
Some small pieces hit
the ground
Damage from the
shock wave
Over 1000 injured
February 14, 2013,
the same day as a
flyby of asteroid 2012
DA14
Apophis Meteor
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Close pass in 2029
April 13, 2036?
Depends on where is
passes in 2029
Comets
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Look like a star with a
tail
Small bodies of ice
and dust
Highly elliptical orbits
Most famous is
Halley’s comet
(1986—2061)
Composition
Parts
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Core/nucleus--head
Coma--spherical
cloud of gas and dust
Tails
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when sunlight causes
the ice to change to
gas
Always flow away from
the sun
Comet ISON in November 2013
Sources—Oort Cloud
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lies beyond
Neptune’s orbit
Matter leftover from
the formation of the
solar system
Long period
comets—take more
than 200 years to
orbit the sun
Kuiper Belt
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Source of short
period comets
Short period comets
have a period of less
than 200 years
Meteoroids
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Small bits of rock and
dust
friction causes them
to burn up as they
enter Earth’s
atmosphere
Shooting stars
Meteor Showers
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When a large number
of meteoroids enter
Earth's atmosphere in
a short period of time
Occur at the same
time each year
Lyrid Meteor Shower
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April 22
Look near Vega
Meteorites
These hit the ground!
Three types
 stony
 Iron
 stony iron