Download Solar System Review - answer key

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Solar System Review
Draw a picture of the following:
1. The position of the Earth and Sun for each season. (Spring, summer, fall,
winter. Make sure you include the tilt of the planet.)
2. The position of the moon, Earth and Sun during a Solar eclipse.
3. The position of the moon, Earth and Sun during a Lunar eclipse.
4. List the planets in order from closest to the sun to farthest.
(My Very Energetic Mother Just Served Us Nine Pizzas)
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune (Pluto)
5. Describe the shape of the orbit of the planets in our Solar System.
The planets orbit around the sun in an elliptical, but nearly circular, pattern.
6. Why are dwarf planets and plutoids not considered planets?
Planets must orbit around the sun, have enough gravity to pull themselves
into a spherical shape, and need to be “alone” in their orbit (not share their
orbit with other objects such as Charon, Pluto’s large moon). Pluto does not
meet the last criteria. In addition, Pluto’s orbit is very much more elliptical
than the other eight planets.
7. Where are most asteroids found in our Solar System?
Most asteroids in our solar system are found in an area between the orbits
of Mars and Jupiter. This area is known as the Asteroid Belt.
8. What is a comet? (Describe its orbit.)
Comets are like “dirty snowballs”: a small nucleus of rock, ice, and frozen
gases. Comets start their journey in the Oort cloud and are knocked out of
it by the gravitational pull of other objects. They then begin a highly
elliptical orbit around the sun. As they come closer to the sun, a coma (long,
fiery tail) develops.
9. What defines a year on any planet? A day?
A year is defined by the time it takes a planet to revolve around the sun one
time. A day is defined as the time it takes the planet to make one complete
rotation on its axis.
10. As the mass of an object increases does the gravitational force
increase or decrease? Why?
As the mass of an object increases, the gravitational force it exerts on
other objects increases. The amount of gravity an object has depends
directly on its mass.
11. As the distance between two objects increases does the
gravitational force increase or decrease? Why?
As the distance between two objects increase, the gravitational pull
between them decreases. The amount of gravitational pull is inversely
proportional to distance.
12. What force keeps the planets from crashing into the Sun?
Inertia, the force that keeps an object moving in a straight line until a force
acts upon it, keep the planets from being overcome by the Sun’s gravity.
Inertia and gravity are in perfect balance.
13. What force keeps the planets from continuing to travel in a
straight path in space?
Gravity (specifically from the Sun) keeps the planets in their orbits.
14. Name three natural satellites of the Sun. (What makes these a
natural satellite?)
All of our planets are natural satellites of the Sun. Any object that orbits
around another one is considered a satellite. A natural satellite is a nonmanmade object.
15. What makes up the constellations?
A constellation is an arbitrary formation of stars perceived as a figure or
design, especially one of 88 recognized groups named after characters from
classical mythology and various common animals and objects.
16. Do we see the same constellations throughout the year? Why or
why not?
We do not see the same constellations throughout the year because Earth is
pointed towards different parts of the galaxy at different times of the
year.
17. What direction do the constellations appear to move? Why?
The constellations appear to move counter-clockwise around Polaris (the
North Star). They appear to move because of the rotation of the Earth.
They seem to rotate around Polaris because the axis of the Earth is pointed
towards it.
18. Do we see the same constellations as those who live in the
Southern Hemisphere? Why or why not?
The northern hemisphere sees mostly different constellations than the
southern hemisphere because they are pointed in opposite directions.
However, some constellations appear in both hemispheres.
19. Why don’t solar and lunar eclipses occur more often?
Solar and lunar eclipses don’t occur every month because the moon’s orbit is
at a tilt (about 5º) to the Earth’s orbit around the Sun.
20. About how long does it take the moon to revolve around the
Earth?
It takes the moon about 28 days to orbit once around the Earth.
21. Why do we see different phases of the moon? (New, first
quarter, full, third quarter)
We see different phases of the moon because, as it orbits about the Earth,
different amounts of it appear to be illuminated by the Sun.
22. What causes the tides? Draw a
picture and label the high and low
tides. (Include the Sun, Earth and
moon)
Tides are caused by the gravitational pull
of the Sun and moon on the water on
Earth.
23. Do we always see the same side of the moon? Why or why not?
It takes almost the same length of time for the moon to rotate once on its
axis as it does for it to revolve once around the Earth. This means we
always see (almost) the same side of the moon facing towards the earth.