Download Our Solar System Study Guide Answers

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Our Solar System Study Guide - Answers
The Earth and the Sun: pages 322 – 326
1) The force that draws Earth towards the Sun is ___ gravity ________________. It is a force of attraction, or
pull, between any two objects.
2) The strength or pull of gravity is affected by the total __ mass ________________ of the objects and by the
___ distance ________________________ between them. If you wanted to decrease the pull of gravity
between two objects, how would you do it? ____ Either find a way to make the masses smaller or place the
objects further apart ________________________________________________
3) An __ orbit ___________ is the path a planet or object takes around another object.
4) The two forces that work together to keep Earth in orbit around the Sun, instead of flying off into space
or being pulled into the sun, are __ gravity ______________ and __ inertia ___________. Earth’s nearly circular
orbit is called an ___ ellipse _____________.
5) Is Earth always the same distance from the Sun? ___ No _______
6) A ____ revolution ________________ is one complete trip around the Sun. Earth makes this trip in one
year or ___ 365 ¼ ______ days or __ 12 ______________ months. How many months would it take Earth to go
half-way around the Sun? ___ 6 months ______________
7) The angle at which sunlight hits Earth changes during a year because Earth’s axis is __ tilted ________
about 230. An ___ axis ________ is a straight line about which an object spins.
8) The ___ seasons _____________ are caused by the tilt of Earth on its axis.
9) During winter in the Northern Hemisphere, the Northern Hemisphere is titled __ away _____________
from the Sun. It does not receive as much direct, concentrated sunlight and temperatures are _ low ______.
10) During summer in the Northern Hemisphere, the Northern Hemisphere is angled towards the sun, so the
heat energy of the sunlight is more ____ concentrated _________________ and direct. The ground receives
more heat energy, and the ___ temperatures _________________ are warmer.
11)Seasons in the Northern and Southern Hemispheres are always __ opposite _______________ because the
tilt of Earth’s axis always points in the same __ direction ______________. So when it is winter here in the
U.S.A., it would be __ summer _____________ in Brazil, and when it is spring in Australia, it would be __ fall
_________ in England.
12) In ___ spring ___________ and ___ autumn _______ both hemispheres receive equal warmth from the
Sun, making mild temperatures.
13) Earth spins in a circle on its axis. One __ rotation _______________ is a complete spin on its axis. Earth
makes one rotation every __ day ______, or __ 24 ___ hours.
14) At any point half of Earth faces the Sun and is in ___ daylight _____________. We call this day. At the
same point, half of Earth faces away from the Sun and is in ____ darkness __________. We call this night.
15) Objects in the sky, like the sun, appear to rise in the _ east _____________ and set in the __ west ____. This
is because as Earth rotates from __ west ________ to __ east _____ objects in the sky appear to move in the
direction opposite Earth’s movement.
The Earth and the Moon: pages 332 – 336
16) On July 20, 1969, astronaut ___ Neil Armstrong __________________ was the first person to walk on the
moon.
17) Why are there no winds and no weather on the Moon? ___ it has no atmosphere __________________
18) The Moon’s surface contains ___ craters ___________, rills (valleys), __ maria ______________, and
mountains that can be seen. (Use the caption on page 332)
19) The side of the Moon that faces the __ Sun __________ is always lit by sunlight. As the Moon ________
revolves _____________around Earth, different amounts of light reflect from the Moon’s surface to Earth,
and the Moon appears to change __ shape ______________.
20) During a ___ full __________ moon phase, you can see the entire half of the Moon that is lit by sunlight.
During a __ new ____________ moon phase, the lit side of the Moon is facing away from Earth.
21) A ___ phase ______________ of the Moon is the appearance and shape of the Moon as you see it at a
particular time.
22) The time from one phase of the Moon until the next time the Moon reaches the same phase is _ 29.5 __
days or about one month. This is the time that it takes the Moon to revolve completely around Earth.
23) Label the phases of the Moon below as seen from Earth. Draw arrows to show the correct order from
one phase to the next.
New Moon
Waxing Crescent
Waning Crescent
First Quarter
Last Quarter
Waxing Gibbous
Waning Gibbous
Full Moon
24) An ____ eclipse _______________ occurs when one object moves in front of another object in space.
25) A __ solar ___________ eclipse occurs when the Moon passes directly between Earth and the Sun. The
moon casts a ___ shadow ______________ on Earth when this happens. People on Earth see darkness move
across the __ Sun ________. This can only occur during a __ new _____ __ moon _________ phase.
26) A ___ lunar _____________ eclipse occurs when the Moon moves into Earth’s shadow and is no longer
reached by direct sunlight. When this happens, Earth is between the __ Sun ____________ and the Moon.
This happens only during a __ full _______ ____ moon __________ phase.
27) Why do new moons and full moons occur once a month, but eclipses occur less frequently? __ The
Moon’s orbit moves above and below an imaginary line between Earth and the Sun, so it doesn’t travel
exactly between Earth and the Sun. ________________________________________________
28) The area where the sun is completely blocked during an eclipse is called the __ umbra _____________.
The area around where light is not completely blocked is called the ___ penumbra ___________________.
29) Label each picture as either a solar eclipse or a lunar eclipse.
______Lunar Eclipse ______________
____ Solar Eclipse __________________
30) The pull of ___ gravity ______________ between Earth and the Moon and between Earth and the Sun
causes a bulge on the surface of Earth. The pull causes the ___ tides ________________, or the rise and the fall
of the ocean’s surface.
31) The pull of gravity causes ocean water to bulge on the side of Earth facing the __ Moon __________. A
matching bulge occurs on the side opposite as well. This causes __ high _________ tides at both locations. __
Low _____________ tides occur halfway between high tides. Most oceans have __ two ______ high and __ two
_____ low tides every day.
32) ____ Spring _____________ tides occur during new and full moon phases when the Sun and the Moon line
up and pull in the same direction. This causes higher high tides and lower low tides.
33) When the Sun and the Moon pull in different directions it can cause high tides that are lower than usual
and low tides that are higher than usual. This tides are called __ neap ________________ tides, and they can
occur during the first quarter and last quarter moon phases.
The Planets: pages 342 – 350
34) A ____ solar ______________ ____ system ___________ is mad of a star and the objects that orbit around
it. A ___ planet __________________ is a large object that orbits a star. A __ moon _________ is a natural
object that orbits a planet.
35) How many planets in our solar system have no moon? __ 2 _____
36) A ___ comet _____________ is a mixture of frozen gases, ice, dust, and rock that moves in an elliptical
orbit around the sun. An ___ asteroid _______________________ is a rock that revolves around the sun.
The asteroid belt is located between ___ Mars ________________ and __ Jupiter _______________.
37) A ___ meteoroids _______________________ is a small object in the solar system. If it crosses paths with
Earth and enters Earth’s atmosphere, it is called a __ meteor ________________________. If it lands on the
ground, it is called a ____ meteorite ______________________.
38) The ___ inner _________________ planets are made mostly of rock. Because of this they are called the
____ terrestrial _________________________ planets. They have few or no moons, and none of them have
_____ rings ___________________. These planets are ___ Mercury _____________ , __ Venus ________ , ____
Earth ___________________ , and ___ Mars __________________ .
39) Which planets have no moon? __ Mercury and Venus _____________________________________
40) Which planet has the smallest mass in our solar system? ___ Mercury ________________________
41) On __ Venus ______________, a day is longer than a year.
42) Because it has not atmosphere, __ Mercury _________________ has extremely high day temperatures
and extremely low night temperatures even thought it is the closest to the Sun.
43) The outer planets are __ Jupiter ____________________ , ___ Saturn _______________________ , ____
Neptune ______________________ , and ___ Uranus ___________________ . They are made mostly of ___ gas
__________. They are much ___ larger ___________________ than the inner planets. All of the outer planets
have rings and many ___ moons ______________.
44) Which two planets have the most moons? ___ Jupiter and Saturn _____________________________
45) Which planet has the greatest mass? ____ Jupiter __________________________
46) The __ days _______ on the outer planets are very short because they spin very rapidly on their axis.
47) Which planet has the greatest gravity? ____ Jupiter ______________________
48) ____ Uranus ________________________________ is blue-green in color due to methane in the planet’s
upper atmosphere.
49) One of Neptune’s moons, ___ Triton ______________________, is larger than Pluto.
50) Pluto is a __ dwarf __________________ planet. Two other objects classified like this are _ Ceres ____ and
__ Eris ______________.
51) The ____Great ______________ __ Red ____________ ___ Spot ________ is a huge storm on Jupiter that has
been blowing for over 400 years.
52) Mars has ____ two ________________ moons.
53) Which moon of Jupiter is the largest in the solar system and is larger in diameter than Pluto and
Mercury? _____ Ganymede _____________________
54) Many moons have __ craters __________________, bowl-shaped holes that form when small objects in
space collide with large objects.
55) Two small rovers, Spirit and Opportunity, explored the surface of ___ Mars _______________ taking
pictures and examining the rocks and soil.
__B__ 56) Which statement explains the position of the side of Earth where it is night?
A. The side of Earth is facing the moon.
B. The side of Earth is facing away from the sun.
C. The side of Earth is being blocked by the moon.
D. The side of Earth is between the sun and the moon.
The following table lists several characteristics of each planet in the solar system.
_B_ 57) What is the connection between the distance from the sun and the period of revolution?
A. The planets farther from the sun have longer days.
B. The planets farther from the sun have longer years.
C. The planets closer to the sun have longer days.
D. The planets closer to the sun have longer years.
The following table lists several characteristics of Venus and Neptune.
_B_ 58) Which explanation describes the difference in temperature between the two planets?
A) Rocky planets are cooler than gaseous planets. B) Venus is warmer because it is closer to the sun.
C) The gases of Neptune allow for heat to escape. D) Neptune is colder because it rotates faster on its axis.