Space Junk

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TCAP Grades 4–5 Writing Practice Task I
Prompt
Read two texts about space debris:
“Space Junk” by Tony Helies and “Space Waste” by Laura
Modigliani
Write an essay that explains how space debris occurs and the
problems it can cause. Be sure to use examples from both texts to
support your explanation. Follow the conventions of standard
written English.
Text 1
Text 1 Introduction In “Space Junk” by Tony Helies, the
author discusses sources of space debris. Please read “Space Junk.”
Space Junk by Tony Helies
There’s a mess up there.
The astronauts living and working in the International Space
Station were worried. Two hundred and forty miles above Earth,
the space station was on a collision course—with a runaway tool.
Three days before, on March 11, 2001, astronaut James Voss had
1
dropped a large vise while he was on a space walk. The vise had
floated away. Now it was back, looming ahead. Mission Control
ordered the astronauts to fire the rockets and move the space
station to a higher orbit. The space station avoided a collision, but
the vise is still up there, part of a large collection of space junk
orbiting Earth.
Until 1957, the only thing orbiting Earth was the Moon. But on
October 4 of that year, the Soviet Union launched a rocket that
placed a satellite named Sputnik in orbit. That launch started a
space race between the Soviet Union and the United States. Over
the years, those two nations put more than 4,000 satellites into
orbit. Today, many nations and private companies put satellites in
space.
2
Satellites are used for communications, television transmission ,
research, and spying. But satellites don’t work forever. Of the
roughly 2,500 satellites still in orbit, only a fraction are still
working. The rest are space junk.
The rockets that launch these satellites become space junk, too.
Many contain unused fuel, and after many years the stresses of
space can cause them to explode. About six of these rockets
explode every year, shattering into thousands of pieces and further
cluttering space.
Dropped in Space
3
But not all of this orbiting debris is old satellites and rockets. Just
as people litter down here on Earth, astronauts litter in space, too.
It started with the first American space walk in 1965. Astronaut
Edward White lost a glove, which went into orbit around Earth.
The next year astronaut Michael Collins fumbled a camera, which
also drifted off into space. In 1971, during a space walk by Apollo
astronauts, a toothbrush and comb escaped through an open hatch.
In 1984, a power screwdriver was dropped by James Van Hoften.
It, too, joined the cosmic clutter.
There are now 4,000,000 pounds of man-made stuff zooming
around Earth, including more than 100,000 objects bigger than a
thumbtack. Some are working satellites, but the rest is junk.
Dangerous junk.
Space junk travels fast. A piece of debris orbiting 240 miles above
us travels about 17,000 miles per hour. At that speed, even a small
object can cause a lot of damage.
Collisions in Space
Fortunately, there is a lot of space up there, but collisions do
happen. In July 1996, an old rocket motor glanced off a satellite
and damaged it. Another time, the Mir (Meer) space station was hit
so hard by debris that the astronauts could see the dent from inside.
Even very small objects can cause a lot of destruction when they
are traveling at great speed. In 1983, a speck of white paint hit one
of the windows of a space shuttle, cutting a hole in the outer layer
of the window glass. Imagine what a chunk of metal the size of
your fist would do.
Some space junk falls back toward Earth, and most of it burns up
in the atmosphere before it reaches the ground. That’s what
happened to Edward White’s glove, so at least astronauts don’t
have to worry about being hit by a runaway piece of clothing. But
most orbiting debris stays up there for many years.
The problem is getting worse. Every month a couple more
satellites are launched.
What Can We Do?
How can we keep space travelers and satellites safe? To protect
our astronauts, the U.S. Space Command tracks 9,800 of the
largest pieces of space junk. Whenever they discover debris on a
collision course with a space station, a shuttle, or a satellite, they
notify NASA and other space agencies. Then the astronauts or
satellite can move out of the way.
A long-term solution is to stop littering in space. For example,
rockets can be designed to fall back toward Earth and burn up in
the atmosphere. And NASA now plans for all new satellites to be
removed from orbit after their useful life. Unfortunately, there are
no international laws controlling junk in space. Perhaps in the
future such laws will limit the amount of orbiting garbage. Until
then, our astronauts will have to drive carefully.
1
vise: a tool used to hold an object while work is being done on it
2
3
transmission: the process of sending information
debris: scattered material
Text 2
Text 2 Introduction
In “Space Waste” by Laura
Modigliani, the author discusses the dangers caused by space
debris crashing into satellites or the earth. Please read “Space
Waste.”
Space Waste by
Laura Modigliani
Scientists explore ways to deal with the junkyard in outer space.
.
1 In September, a six-ton satellite about the size of a bus fell
toward Earth. It had been launched .
2 into space in 1991. The satellite broke into pieces as it passed
through Earth’s atmosphere. Bits .
3 of it were found in western Canada. The good news is that no
one got hurt when the pieces .
4 crashed to the ground. .
5 Space trash falling to Earth isn’t unusual. In fact, a piece of
junk about as big as the satellite .
6 drops out of orbit about once a year. Smaller pieces fall far
more often. .
7 And a lot more trash is still floating out in space. All of that
spinning debris can be dangerous. .
8 Pieces of space junk can crash into expensive spacecraft or the
International Space Station (ISS). .
9 That can cause major damage. Scientists are working to track
and limit the growing cloud of .
10 junk above Earth. .
11 Objects in Orbit .
12 About 1,000 working satellites are up in space. Some are
used by the military. Others help .
13 forecast the weather. Communications satellites beam TV,
cell phone, and Internet signals down .
14 to Earth. When satellites become outdated or can no longer
function, they become space junk. .
15 But the orbiting trash isn’t just old satellites. It also includes
other human-made objects, from .
16 rocket parts to tools dropped by astronauts. . . . .
17 There are tens of millions of tiny pieces of trash swirling
around Earth right now. More than .
18 22,000 of those objects are bigger than a baseball—and they
move pretty fast. Space debris .
19 whizzes around at speeds of up to 18,000 miles per hour. .
20 The amount of space trash soared in 2007. That’s when China
tested a new missile by blowing .
21 up an old weather satellite. The explosion created thousands
of pieces of space junk. The trash .
22 heap got even bigger in 2009. A working U.S. satellite and a
nonworking Russian satellite .
23 accidentally crashed into each other. Pieces from both were
sent tumbling. .
24 Crash Course .
25 The ISS can get hit by tiny pieces of junk . . . and not suffer
much damage. But it has to be .
26 moved to avoid collisions with pieces not much bigger than
that. In April, NASA, the U.S. .
27 space agency, moved the ISS to dodge a piece of debris
created by the 2009 collision. .
28 “Even a half-inch piece of debris would put a very large hole
in the International Space Station,” .
29 says Nicholas Johnson. He’s the chief scientist at the NASA
Orbital Debris Program Office. .
30 Junk hangs around in space until it eventually burns up in
Earth’s atmosphere or falls back to the .
31 planet. On average, one piece of debris reaches Earth each
day. Most objects are very small and .
32 not a great threat to humans. .
33 “There is some risk,” Johnson says. “But for half a century,
no one’s been hurt.” .
34 Tracking the Trash 4
.
35 NASA works with the U.S. military to keep track of the
larger space junk. They track this trash .
36 from the ground, using radar, powerful telescopes, and a
special satellite. Scientists use the .
37 information they gather to figure out whether they need to
move spacecraft or the ISS to avoid a .
38 collision. .
39 President Barack Obama has pledged to work with other
countries to stop littering in space. He .
40 has assigned NASA and the U.S. Department of Defense to
come up with ways to get rid of the .
41 space garbage. But their ideas are years away from reality. .
42 Meanwhile, as more collisions happen and as humans keep
sending stuff into space, the junk .
43 cloud continues to grow. .
44 “We will have to take the next step to clean it up,” says
Johnson. “It’s not going away on its .
45 own.” 1
vise: a tool used to hold an object while work is being done on it
2
transmission: the process of sending information
3
debris: scattered material
4
collisions: crashes, often at high speeds

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