Transcript Comparative Planetology

Interdisciplinary field of astronomy and geology attempting to
discover and explain differences between planets in properties
such as climate and interior structure.
Contents
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Planets
Craters
Volcanism
Existence of Water
Jovian Storms
Comparison of Planets
Planets
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Craters
Craters accumulate over
time. By studying them we are able
to determine a rough age of the
surface of the planet or moon. They
are most commonly caused by the
impact of a meteorite or other
celestial body. The largest craters
can be found on Venus, but small
craters can be found on Mercury,
Mars, and the moon.
Craters can range in size
from 2km wide to smaller than
grapes.The small craters cannot be
found on Earth. The other planets are
not protected by an atmosphere like
ours and even the smallest space
debris reaches the surface.
Volcanism
Volcanic activity
can be found on both
Venus and Earth. Lava
on Earth can travel far
before it cools but on
Venus the lava cools
faster and has less
time to travel due to
the colder ambient
temperature.
We can
document the
subsurface core
activity and compare it
to that of Earth. The
most geologically
active object in our
solar system is Io.
Existence of Water
On Earth life as we
know it needs water to survive.
Observations of other planets
and moons show no signs of
current exposed liquid water.
However, some show signs that
suggests that liquid water was
once present. We have
observed polar ice caps similar
to ours on Mars.
A possible channel
system showing signs that
water once flowed over the
surface of Mars has also been
documented. Under the icy
surface of Europa, smallest of
the Galilean moons, we believe
there to be an ocean. Also on
Ganymede we believe in the
existence of an ocean
sandwiched between two layers
of ice.
Jovian Storms
Although the Jovian planets are made
mainly of gas and lack a clearly defined
surface they are similar to Earth in the sense
that there are storms present in the
atmospheric gas. Study of the Jovian planets
helps us understand how our own solar system
formed through observation of the formation of
their moons.
Comparison of Planets
Through the observation and comparison of similarities
in our solar system, we are able to expand our knowledge and
understanding. By observing the craters on other object we can
learn more about the history of our solar system and the future
possibilities of earth.
For example comparing Earth to Venus we are
protected from much space debris by our atmosphere and
without it we might have an appearance comparable to Venus.
We can learn more about subsurface core activity through our
observations of Io and Venus.
We search for extraterrestrial life by looking for liquid
water, which is necessary for life on earth, on other planets and
moons. We also look for signs that water existed by looking for
familiar features on the surface of the object, such as cannals.
By comparing and studying our solar system we are
able to gather new information and make further progress in
our reach into outer space.