Download Constructing a Solar System

Exploring Our Solar System
What astronomical objects are needed to construct a solar system?
Now that you have a list of objects that should include a star, planets, moons,
asteroids, and comets, what type of motions do the objects have within the solar
system?
Here you might want to consider using the terms revolution and rotation.
Revolution – one object moving in an elliptical or near circular path around
another object
Rotation – an object spinning on an axis
Let’s consider the distance from the Sun, our star, and size of the planets in our
solar system. We want to do a relative comparison or scaling of the distances and
the diameters.
x 106 km
km
From the data, how do the distances from the Sun and planet diameters compare?
Planetary Scaling Excelet Activity
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The scaling of the distance will be based on the Earth-Sun distance, which is
referred to as one astronomical unit or 1 AU. The scaling of the diameter is
relative to the Earth’s diameter.
Open the interactive Excel spreadsheet to get the data:
http://academic.pgcc.edu/~ssinex/excelets/planetary_scaling.xls
Click on the scaling tab to view the distance and diameter data for the planets.
Now enter the appropriate numbers into the yellow cells on the scaling tab. The
spreadsheet will automatically do the math for you.
From the scaled data, how do the distances from the Sun and planet diameters
compare?
You may want to view the graphical scaling tab to see a plot of relative planet
diameter against the relative distance from the Sun.
Solar systems form from swirling clouds of
material where the massive center has a star
form. The cloud would look somewhat like a
hurricane. This is an image of Ivan in 2004
(from NOAA) in the Gulf of Mexico.
What direction is it rotating – CW (clockwise)
or CCW (counter-clockwise)?
On the scaling tab, click on the check boxes to get the add direction of motion and
add composition data to be visible. Do all the planets revolve in the same
direction? If so, what direction CW or CCW?
Planetary Scaling Excelet Activity
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Do all the planets rotate in the same direction?
The physics of the solar system formation should have created all the objects
revolving and rotating in the same direction. Impact may have been the cause of
some planets change in their direction of rotation.
The solar system gets divided into the inner and outer planets. Where would you
make the divide? Why?
List the planets in each.
inner solar system
outer solar system
Are there other solar systems for astronomers to study?
What is an exoplanet? Go to the Exoplanets website http://planetquest.jpl.nasa.gov/
How many exoplanets have been discovered? Are they earth-like or giants like
Juptier?
Planetary Scaling Excelet Activity
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When you observe a full Moon, you see essentially the
same image or face of the Moon each time. Does the
Moon rotate? Explain your choice.
The Full Moon -Credit: Lick Observatory
How do you know that the Earth rotates once every 24 hours?
Pluto has been demoted from its planetary status. Pluto is now classed as a dwarf
planet. From looking at the data in this activity, can you suggest reasons why it
was demoted?
Planetary Scaling Excelet Activity
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