UNIT 5 WEEK 4
Read the article “Voyage to the Planets” before answering Numbers 1
through 5.
Voyage to the Planets
A voyage to Jupiter, the largest planet in our solar system, takes years. Saturn and
Uranus are even farther away. A voyage to Neptune, in the farthest reaches of the
solar system, takes decades. Such a journey would be too complicated and
dangerous for even the most highly-trained astronauts, but scientists have
developed technology that can take them to distant planets without leaving Earth.
How are scientists able to take this voyage to the planets? They developed
unmanned space probes that can safely travel to Jupiter and Saturn. These probes
collect information using sophisticated scientific instruments. With their superior
technology, they can send data and photos back to Earth.
Copyright © McGraw-Hill Education
Two unmanned space probes, Voyager I and Voyager II, began missions in 1977.
Both Voyager space probes were launched from the Kennedy Space Center in
Florida. The launches were planned to take advantage of the unusual positions of
the planets. Once every 175 years, Jupiter, Saturn, Uranus, and Neptune line up
in space. Because of this alignment, the Voyager probes would be able to fly past
Jupiter and Saturn. And if scientists were lucky, one of the probes might continue
travelling even farther to Uranus or Neptune.
Voyager II was launched first in August of 1977. One month later, Voyager I was
launched, but with a different flight path that would get it to Jupiter sooner than
Voyager II. In March of 1979, nineteen months after its launch, Voyager I reached
the first destination, passing by the planet Jupiter. Voyager II flew by Jupiter in
July, four months later.
The space probes sent back incredible pictures of the solar system’s largest planet.
Scientists got a close look at Jupiter’s famous Great Red Spot. They also learned
about Io, one of Jupiter’s moons. Voyager I discovered turbulent, or violent,
volcanic activity on Io, which was causing great disturbances on its surface.
In November of 1980, a year and a half after its exploration of Jupiter, Voyager I
flew by Saturn. Voyager II followed in August of 1981. Both space probes sent
photos of Saturn’s magnificent ring system, one of the solar system’s most
stunning sights. Scientists also received data about Titan, Saturn’s largest moon.
GO ON
Weekly Assessment • Unit 5, Week 4
Grade 6
277
UNIT 5 WEEK 4
The original mission of the Voyager space probes was to collect data about Jupiter
and Saturn. But after the probes passed Saturn, NASA scientists made a
remarkable discovery. Voyager II’s flight would continue unexpectedly, and it
would travel past both Uranus and Neptune! For the first time ever, scientists on
Earth would get a close glimpse of the distant planets.
In January of 1986, nearly 10 years after its launch, Voyager II flew by Uranus. The
space probe collected information about the atmosphere that surrounds the
planet. It also sent back data about Uranus’s mysterious dark rings. Then three
and a half years later, in August of 1989, Voyager II made its closest approach to
Neptune. It was the space probe’s last visit to a planet in our solar system, but it
was not done yet.
GO ON
278
Grade 6
Weekly Assessment • Unit 5, Week 4
Copyright © McGraw-Hill Education
As Voyager II passed Neptune, Voyager I was heading towards the outer edges of
the solar system. Finally, after more than three decades in space, Voyager I left the
solar system. It continues to transmit what it learns in deep space back to Earth.
Voyager II followed its own route into deep space as well. The probes are expected
to travel billions of miles away from the Sun. Scientists expect to receive messages
from the Voyager probes
until 2020. After thirty
years of travel, they will no
longer be able to generate
the electrical power needed
to continue sending
transmissions back to
Earth. Until then, who
knows what wondrous
discoveries await!
Name:
Date:
Now answer Numbers 1 through 5. Base your answers on “Voyage
to the Planets.”
1
Which sentence best explains how the author organized the text?
A by explaining causes and effects
B
by telling events in sequential order
C by describing a problem and its solution
D by comparing and contrasting two things
2
This question has two parts. First, answer part A. Then, answer part B.
Part A: Read the sentences from the text.
These probes collect information using sophisticated scientific instruments.
With their superior technology, they can send data and photos back to Earth.
What does the word sophisticated tell about the instruments?
A They are new.
B
They are small.
C They are beautiful.
Copyright © McGraw-Hill Education
D
They are advanced.
Part B: Which phrase in the sentences provides a clue to the meaning
of sophisticated?
A “collect information”
B
“scientific instruments”
C “superior technology”
D
“back to Earth”
GO ON
Weekly Assessment • Unit 5, Week 4
Grade 6
279
Name:
3
Date:
Circle the word in the paragraph that is used to restate what turbulent means.
The space probes sent back incredible pictures of the solar system’s largest
planet. Scientists got a close look at Jupiter’s famous Great Red Spot. They
also learned about Io, one of Jupiter’s moons. Voyager I discovered
turbulent, or violent, volcanic activity on Io, which was causing great
disturbances on its surface.
4
This question has two parts. First, answer part A. Then, answer part B.
Part A: Why does the author describe the sequence of Voyager II’s journey
after it passed Saturn?
A to show how the mission of Voyager II changed
B
to show what scientists hope to learn about deep space
C to show how far away Uranus and Neptune are from Earth
D
to show what Voyager II discovered about Uranus and Neptune
Part B: Which sentence from the text best supports your answer in part A?
A “Both space probes sent photos of Saturn’s magnificent ring system,
one of the solar system’s most stunning sights.”
B
“Scientists also received data about Titan, Saturn’s largest moon.”
C “The original mission of the Voyager space probes was to collect data
about Jupiter and Saturn.”
“Voyager II’s flight would continue unexpectedly, and it would travel
past both Uranus and Neptune!”
GO ON
280
Grade 6
Weekly Assessment • Unit 5, Week 4
Copyright © McGraw-Hill Education
D
Name:
5
Date:
Select two results of Voyager II’s journey beyond Saturn.
A the first photographs of Saturn’s rings
B
the discovery of volcanic activity on Io
C new information about Uranus’s dark rings
data about the temperatures found on the Sun
E
data about the atmosphere surrounding Uranus
F
new information about Jupiter’s Great Red Spot
Copyright © McGraw-Hill Education
D
GO ON
Weekly Assessment • Unit 5, Week 4
Grade 6
281
UNIT 5 WEEK 4
Read the article “A Planet No More” before answering Numbers 6 through 10.
A Planet No More
People have always been interested in learning about planets. The planets nearest
to Earth in the solar system—Mercury, Venus, and Mars—can be seen with the
naked eye, and so can Jupiter and Saturn, the largest planets. But what about the
planets that are more distant from the sun? Because they cannot be seen without
a telescope, for a long time no one knew they existed.
The planet Uranus was first identified in 1781, and Neptune followed in 1846.
Scientists searched for a ninth planet for years. Then in 1930, a 24-year old Kansas
astronomer named Clyde Tombaugh discovered an object at the outer edge of the
solar system. The tiny body was given the name Pluto. Was Pluto the longexpected ninth planet? Based on what they learned from the other discoveries,
scientists decided that it met the requirements to be a planet, and Pluto was
introduced as a new addition to the solar system.
For the next 76 years, Pluto was considered the solar system’s ninth planet, but
Pluto was very different from the gas giants, or huge planets made up primarily of
gases. Jupiter, Saturn, Uranus, and Neptune are at least ten times the size of Earth
and made of mostly gases, rather than rock. Pluto, on the other hand, is much
smaller than Earth, solid, and very icy.
Around the time Nix and Hydra were first identified, scientists were using
powerful new telescopes to discover other bodies in the Kuiper Belt. The Kuiper
Belt is a region of space beyond the orbit of Neptune, where Pluto orbits. Many of
the bodies found there were very similar to Pluto, and one of the objects found in
the belt, an icy body named Eris, was about the same size as Pluto.
The discovery of more and more bodies in the Kuiper Belt raised questions. Could
Eris possibly be a tenth planet? If not, how could Pluto—which Eris closely
resembled—hold the title of planet? Scientists began to rethink Pluto’s status
as a planet.
GO ON
282
Grade 6
Weekly Assessment • Unit 5, Week 4
Copyright © McGraw-Hill Education
In 1978, scientists detected another body near Pluto that they named Charon.
They determined that Charon was a moon of Pluto. However, many scientists
referred to Charon and Pluto as a double planet system because the two bodies are
so close in size. In 2005, scientists discovered two additional moons orbiting
Pluto. They named these moons Nix and Hydra.
UNIT 5 WEEK 4
In 2006, a group of scientists from the International Astronomical Union met to
answer these questions. They decided that a new system was needed to classify
planets. To be a planet, scientists said, a body must travel in an orbit around the
sun. It must have enough mass to clear objects out of its path in space. And it
must have enough gravity to pull itself into a sphere. Mercury, Venus, Earth,
Mars, Jupiter, Saturn, Uranus, and Neptune are all planets.
Pluto and Eris would now belong to a new category, a type of body called dwarf
planets. Dwarf planets orbit the sun, traveling in regions such as the Kuiper Belt,
but they do not have the gravity or mass that planets have. After much debate,
scientists concluded that Pluto was not the ninth planet after all.
Copyright © McGraw-Hill Education
Many people believe that Pluto should still be the ninth planet. Most scientists
agree, however, that Pluto is indeed a dwarf planet. Whatever Pluto is, many more
bodies remain to be discovered at the edge of the solar system. Since 2006,
scientists have found a multitude of icy bodies in the Kuiper belt that might be
dwarf planets. As science advances, more will be learned about the planets and
what else lies deep in outer space.
GO ON
Weekly Assessment • Unit 5, Week 4
Grade 6
283
Name:
Date:
Now answer Numbers 6 through 10. Base your answers on “A Planet No More.”
6
This question has two parts. First, answer part A. Then, answer part B.
Part A: Why does the author explain the sequence in which Uranus, Neptune,
and Pluto were discovered?
A to show why scientists thought Pluto was the ninth planet
B
to show how Pluto is different from Uranus and Neptune
C to show why Uranus and Neptune were discovered first
D
to show how far away from Earth these planets are
Part B: Which detail from the text best supports your answer in part A?
A “The planet Uranus was first identified in 1781, and Neptune
followed in 1846.”
B
“Scientists searched for a ninth planet for years.”
C “Then in 1930, a 24-year old Kansas astronomer named Clyde
Tombaugh discovered an object . . .”
D
7
“Based on what they learned from the other discoveries, scientists
decided that it met the requirements to be a planet . . .”
Read the paragraph from the text.
What does the word primarily mean?
A carefully
B
mostly
C originally
D
slowly
GO ON
284
Grade 6
Weekly Assessment • Unit 5, Week 4
Copyright © McGraw-Hill Education
For the next 76 years, Pluto was considered the solar system’s ninth planet,
but Pluto was very different from the gas giants, or huge planets made up
primarily of gases. Jupiter, Saturn, Uranus, and Neptune are at least ten
times the size of Earth and made of mostly gases, rather than rock. Pluto,
on the other hand, is much smaller than Earth, solid, and very icy.
Name:
8
Date:
Read the paragraph from the text.
In 1978, scientists detected another body near Pluto that they named
Charon. They determined that Charon was a moon of Pluto. However, many
scientists referred to Charon and Pluto as a double planet system because the
two bodies are so close in size. In 2005, scientists discovered two additional
moons orbiting Pluto. They named these moons Nix and Hydra.
How does the author explain the discovery of new bodies near Pluto?
Select two options.
A by describing the effect of the discoveries on the solar system
B
by telling what caused scientists to make the discoveries
C by identifying how the discoveries are related to Pluto
9
D
by identifying how the discoveries compare to Earth
E
by telling how the discoveries solved a problem
F
by describing the discoveries in sequence
Read the paragraph from the text.
Copyright © McGraw-Hill Education
The discovery of more and more bodies in the Kuiper Belt raised questions.
Could Eris possibly be a tenth planet? If not, how could Pluto—which Eris
closely resembled—hold the title of planet? Scientists began to rethink
Pluto’s status as a planet.
What does the word status mean in the paragraph?
A importance
B
popularity
C time
D
title
GO ON
Weekly Assessment • Unit 5, Week 4
Grade 6
285
Name:
10
Date:
Put the events from the text in the correct sequence by numbering them from 1
to 6. Write the correct number in front of each event.
Neptune is identified.
Eris is discovered in the Kuiper Belt.
Pluto is categorized as a dwarf planet.
Charon, a moon of Pluto, is discovered.
Scientists begin to rethink Pluto’s status as a planet.
Many possible dwarf planets are found in the Kuiper Belt.
Copyright © McGraw-Hill Education
STOP
286
Grade 6
Weekly Assessment • Unit 5, Week 4
Name:
Date:
Now answer Number 11. Base your answer on “Voyage to the Planets” and
“A Planet No More.”
Compare and contrast how the authors of both texts present information. How
do the authors provide details about the discovery of different planets and the
scientific data related to them? Support your answer with information from
both texts.
Copyright © McGraw-Hill Education
11
Weekly Assessment • Unit 5, Week 4
Grade 6
287