School Based Activities
School-based activities
Satellites – what are they?
Activities 1 and 2 allow students an opportunity to recall and outline their prior
knowledge about satellites, to pose questions about the topic, to learn from their peers
and to read and discover more about satellite technology. Background information about
satellites is provided on page 11 of the Teacher Notes.
Activity 1: Think, Pair, Share Brainstorming
Aim
To allow students the opportunity to explore, and pose their own questions in, the topic
of satellites.
What you need
• Photocopy for each student: Worksheet 1: Think, pair, share
• Coloured pencils
• Post-it™ notes
What you do
1. Give each student their own copy of the image of Earth. If it can be printed in
colour – this would help students to analyse the image.
2. Give each student a number of Post-it notes so they can write their thoughts on
the notes, and they can be moved or removed as their ideas change throughout
the unit of work.
3. Think - each student begins by brainstorming around the topic of satellites. They
write their thoughts on Worksheet 1. Allow the students a few minutes to work
alone. Remind students that during this process it is not about right or wrong
answers, just about documenting their thoughts. Encourage students to write as
much as they like.
4. Pair – have students now work in pairs, sharing their ideas and understandings
of the topic. They may add new information to their image should they need to.
5. Share – now have students work in groups of four. What information is the same,
what information is different? Have each group write a list of 4 things they think
are true about satellites, and four questions they have about satellites. These
four comments and questions can be shared with the whole class. They could be
left on a poster, and displayed on the wall throughout the topic.
6. Have the students keep their brainstorming sheet. This could be used throughout
the Unit. As the students learn new information, they can use this as a tool to add
new information, answer their own questions and change their ideas. At the end
of the Unit, it can be used for students to reflect on their learning throughout the
topic.
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School Based Activities
Worksheet 1: Think, Pair, Share Brainstorming
Name: …………………………………………………………………
•
Look at this picture. Write as many things as you can about the image. For
example you might write about what you already know about satellites and
questions you have about satellites.
•
Use sticky notes to add more information or questions if you run out of space.
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School Based Activities
Activity 2: Write on the reading
Aim
Students discover more about satellites by reading a text in a way that encourages
reflection.
What you need
• Photocopy for each student: Worksheet 2: Write on the reading
What you do
1. Give each student a copy of Worksheet 2.
2. Students are asked to respond to the text by writing on the worksheet. They can
write questions, statements, or they can disagree or agree with comments made
in the text. By writing on the reading, students engage with the text and are
encouraged to think and question the reading. See below for an example of how
they might do this.
3. After the students have finished reading and writing on the text, have them refer
to their Think, Pair, Share sheet. Allow students to add more information, or
change their ideas.
4. From both of these activities, students may have generated a significant number
of questions about satellites. These questions could be used for the students to
research and contribute information about the topic. Their answers could be
pinned on a wall for all students to read.
Example of student’s work:
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School Based Activities
Worksheet 2: Write on the reading
Everyday thousands of satellites orbit Earth above our heads!
Satellites are objects that orbit another object; they can be natural or
man-made. The Moon orbiting the Earth is a naturally occurring
satellite. The International Space Station orbiting Earth is a man-made
satellite – we call this an ‘artificial satellite’.
The first ‘artificial satellite’ launched was Sputnik 1. It was launched 50
years ago, in 1957, by the Soviet Union. Sputnik 1 was the size of a
basketball, and it took 98 minutes to orbit the Earth. It contained a
thermometer, a battery, a radio transmitter and nitrogen gas. Today
artificial satellites orbiting Earth are more sophisticated than Sputnik.
They can be used to forecast the weather, take pictures, transmit
satellite television, transfer calls over the oceans, monitor bushfires,
floods or cyclones, and they can even be used to give us directions
while driving our cars!
Some satellites orbit the Earth just a few hundred kilometers up. These
satellites, called near-Earth satellites, orbit quickly - it may take only an
hour and a half to orbit Earth! Near-Earth satellites observe many parts
of the Earth in one day, and they can see more detail than a satellite
far away.
Some satellites orbit Earth much further out. At 35,400 km above the
Earth's surface a satellite takes 24 hours to orbit Earth once, which is
the same time it takes the Earth to rotate once on its axis. These kinds
of satellites, called geostationary satellites, always stay above the
same spot on Earth and this make them very useful for weather
observations and communications.
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School Based Activities
Background information
Launching satellites into orbit
Like a rocket travelling to the Moon, the first thing the satellite needs to do is get off
Earth’s surface – and stay off! This happens by launching the satellite on a rocket. The
rocket is launched pointing straight up. When the rocket is high enough, it is tilted to
head the rocket into its correct flight plan.
A satellite’s orbit is the path it travels through space. Some satellites orbit the sun, or
other planets such as Jupiter. EOS satellites orbit our planet Earth. The Eyes on Earth
exhibit has several units designed to help people understand different types of orbits.
Satellite orbits have a variety of shapes. Some are circular, while others are highly
elliptical (egg-shaped). Orbits also vary in altitude. Some circular orbits, for example, are
just above the atmosphere at an altitude of about 250 kilometres, while others are more
than 32,200 kilometres above Earth. The greater the altitude, the longer the orbital
period - the time it takes a satellite to complete one orbit.
A satellite remains in orbit because of a balance between the satellite's velocity (speed
at which it would travel in a straight line) and the gravitational force between the satellite
and Earth. Were it not for the pull of gravity, a satellite's velocity would send it flying
away from Earth in a straight line. But were it not for velocity, gravity would pull a
satellite back to Earth.
To help understand the balance between gravity and velocity, consider what happens
when a small weight is attached to a string and swung in a circle. If the string were to
break, the weight would fly off in a straight line. However, the string acts like gravity,
keeping the weight in its orbit. The weight and string can also show the relationship
between a satellite's altitude and its orbital period. A long string is like a high altitude.
The weight takes a relatively long time to complete one circle. A short string is like a low
altitude. The weight has a relatively short orbital period.
Many types of orbits exist, but most artificial satellites orbiting Earth travel in one of four
types: (1) high altitude, geosynchronous; (2) medium altitude, (3) sun-synchronous,
polar; and (4) low altitude. Most orbits of these four types are circular.
Much of this information was taken from:
www.nasa.gov/worldbook/artificial_satellites_worldbook.html
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School Based Activities
Activity 3: Satellites in orbit
Aim:
To assist students’ understanding of how satellites stay in orbit.
What do you need:
• string
• small weight to attach to the string (soft ball)
• enough room to swing it!
What do you do:
1. Ask the your students the following questions:
a. How does a satellite keep moving around the Earth?
b. Why doesn’t it fly away into space?
c. Why doesn’t it crash down to Earth?
d. How come the satellite doesn’t need to refuel?
2. Explain why a satellite can keep orbiting the Earth without the need to refuel.
3. To demonstrate forces in action when a satellite is orbiting, cut a piece of string
about 1 meter long. Tie a weight to the end of the string (any thing heavy enough
will do – but not too heavy or sharp). Imagine you are the ‘Earth’ and the weight
at the end of the string is a ‘satellite’. Swing the string around you. The string is
acting like gravity – ask the students: how does it act like gravity? If the string
was to break, what would happen to the weight? (It would fly off into space – in a
straight line).
Extension activity:
An online activity called Shoot a cannon ball into orbit ’can be found on the NASA
website http://spaceplace.jpl.nasa.gov/en/kids/orbits1.shtml
This interactive animation demonstrates the relationship between gravity and force with
regards to orbiting Earth.
Background information:
A satellite remains in orbit because of a balance between the satellite's velocity (speed
at which it would travel in a straight line) and the gravitational force between the satellite
and Earth. Were it not for the pull of gravity, a satellite's velocity would send it flying
away from Earth in a straight line. But were it not for velocity, gravity would pull a
satellite back to Earth.
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School Based Activities
Activity 4: The Great Space Race
Aim:
In this activity students investigate forces and chemical reactions which model the
launching of a satellite into orbit.
What you need (each group needs):
• film canister with a lid that snaps
shut
• Alka-Seltzer™ tablets
• Water
• Safety glasses
What to do:
1. Discuss with the students how they think a satellite is launched into orbit. What
does the rocket need to get away from? (Earth’s gravity). How does it do this?
(with a lot of fuel to make it travel really fast!)
2. Explain that they are going to launch model rockets. Students need to take their
kit of rocket equipment outside. Allow the students to have enough to launch the
rockets a few times.
3. Don’t show or tell the students what to do, let them figure it out what they think
they need to do to launch the film canister into the air. Just ensure that students
don’t stand near their ‘rocket’, as the flying projectile may hit them in the face!
4. Allow the students to test their rockets 3 times. They need to get their rocket
ready for the ‘Rocket Race’. They need to not waste their materials (ie: the
limited number of Alka-Seltzer™ tablets), so they need to use their analysing,
discussion and listening skills to ensure that their rocket will be successful in the
race.
5. For the ‘Rocket Race’, each group needs to enter their winning design.
ƒ Awards could be given for:
ƒ Highest rocket
ƒ Fastest to launch
ƒ Longest time spent in the air
ƒ Most creative design (if you allow students to decorate their film canister).
Make sure the students agree to the rules as to how you will judge the highest or fastest.
Discussion questions:
ƒ
Which rocket went the highest? Why?
ƒ
Which rocket launched first? Why?
ƒ
Which rocket stayed in the air the longest? Why?
ƒ
Why did the rockets launch? What was happening inside the film canister? (Gas
pressure builds inside the film canister due to the mixing of Alka-seltzer™ and
water. This action continues until enough pressure blows apart the canister from
its lid. The result is a rocket launch.)
ƒ
How do you think this activity relates to launching a satellite into air? How much
energy do you think is needed to launch a satellite into air?
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School Based Activities
Activity 5: Satellite maths
Name: ……………………………………………………………………………………………
You are travelling in a satellite!
You are
here!
The distance you travel in your orbit
around Earth (called an orbital
circumference)
is:
41330 kilometres
Orbital circumference
(or the distance to go
around this orbit once)
= 41330 kilometres
You are travelling at a speed of:
28000 km/hr (kilometres per hour)
Your space
station is
orbiting 400
kilometres
above Earth!
Use a scientific calculator or spreadsheet program to work out the
answers below.
You must work out each answer in order, so as you can move on to the next answer.
1. How many hours does it take you to travel around the Earth once?
(Hint: distance ÷ speed = time to travel around the Earth)
………………………………………………………………………………………………….
………………………………………………………………………………………………….
2. How many times do you travel around the Earth in:
1 day? (hint: there are 24 hours in one day)
…………………………………………………………………………………………….…..
1 year? (hint: there are 365 days in 1 year)
………………………………………………………………………………………………..
3.
After one year of orbiting Earth, what distance (in kilometres) would you
have travelled in your satellite?
…………………………………………………………………………………………………….
Have a look at real satellites orbiting Earth, and see their orbital path and velocity at:
http://science.nasa.gov/realtime/jtrack/3d/JTrack3D.html
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School Based Activities
Activity 5: Satellite maths Answers
You are travelling in a satellite!
The distance you travel in your orbit
above Earth (otherwise called
an orbital circumference)
is: 41,330 kilometres.
You are
here!
You are travelling at a speed of:
28,000 kilometres per hour
(km/hr).
Orbital circumference
(or the distance to go
around this orbit once)
= 41330 kilometres
Your space
station is
orbiting 400
kilometres
above Earth!
1. How many hours does it take you to travel around the Earth once?
(hint: distance/speed = time)
1.476 hours to get around the Earth once.
2.
How many times do you travel around the Earth in:
1 day? (hint: there are 24 hours in one day)
You will travel around the Earth 16.26 times in one day.
1 year? (hint: there are 365 days in 1 year.)
You will travel around the Earth 5934.9 times in one year.
3.
After one year of orbiting Earth, how many kilometres would you have
travelled in your satellite?
245,289,417 kilometres travelled in 1 year.
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School Based Activities
Activity 6: Crash testing satellites!
When a spacecraft or satellite is launched into space, it can be exposed to all kinds of
harsh conditions. It may be hit by space junk, baked by harsh sun rays, or frozen by
extreme cold! Scientists designing and building spacecrafts and satellites need to ensure
that they build them out of materials that will be able to survive harsh treatment!
Aim:
To assess the ability of various materials to withstand harsh conditions (such as those
experienced by an object being launched into space).
What you need:
• Photocopy for each student: Worksheet 3: Crash testing satellites – scientific
report
• material to test (i.e.: rubber band, aluminium foil, plastic pieces)
• hammer
• vinegar
• glass jar with lid
• water
• detergent
• salt and water
• digital camera
What to do:
1. Put students into groups of no more than 4 (pairs would be best).
2. Each group will need two identical samples of each material to test. One sample
will remain untested (the control), and the other sample will be tested.
3. Give each student a copy of Worksheet 3. This worksheet can be used to
record their results. Ensure that the students write down their prediction before
they do their test.
4. Above is a list of items that could be used to test your sample’s durability. Your
students may choose any of the following (or have their own suggestions)
a. Hit the sample with the hammer
b. Soak it in vinegar (acid)
c. Leave it in the sunlight in a glass jar
d. Soak it in salt and water
e. Soak it in detergent
f. Freeze the object
g. Heat the object (in boiling water) – remember NEVER put metal in the
microwave.
5. Make sure the students keep one control sample to use as a comparison.
6. Each group can write up their results on the worksheet. They may also like to
take digital photographs of their object, before and after. These photos could be
put into a PowerPoint presentation, so they can report to the class about their
experiments.
7. In their report students need to discuss:
a. What they did to their sample material (the method);
b. What happened to their sample material (their observations);
c. Do they think their material would be suitable to build a satellite?
(their conclusion).
This activity was adapted from: http://spaceplace.nasa.gov/en/educators/material_torture.pdf
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School Based Activities
Worksheet 3: Crash testing satellites – scientific report
Name: ……………………………………………………………………………………………..
Prediction: (what do you think will happen?)
………………………………………………………………………………………………………
………………………………………………………………………………………………………
Aim: (what are you trying to find out?)
………………………………………………………………………………………………………
………………………………………………………………………………………………………
Method: (How did you go about doing your experiment?)
………………………………………………………………………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………
Observations / Results: (what happened to your sample? Include a table, a graph or
photograph of your results).
………………………………………………………………………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………
Discussion / Explanation: (why do you think this happened?)
………………………………………………………………………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………
Conclusion:
Do you think this material would be suitable to use to build a satellite? Why or why not?
………………………………………………………………………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………
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School Based Activities
Background information
What can satellites tell us?
Satellites do all kinds of jobs; these are some examples of their different tasks.
Scientific research
Some satellites gather data that is then analysed by scientists back on Earth.
They may gather information about changes on the Earth’s surface, changes in
the Earth’s atmosphere, or even information about planets, stars and other
distant objects in our Universe.
Weather monitoring
Some satellites monitor weather patterns, such as cloud cover, temperature, air
pressure, precipitation and the chemical composition of the atmosphere. This
enables scientists to better forecast the weather, and give early warning alerts for
important events like approaching cyclones.
Communications
Radio signals, television programs, and telephone calls can be transmitted
across the planet via communication satellites.
Navigation
When Captain Cook travelled around the globe, he used a sextan and his
knowledge of the stars and the position of the Moon to navigate. Today satellites
enable pilots, sailors and even car drivers to determine their location on the
planet with incredible accuracy, and more easily navigate their way using GPS
(global positioning system).
Observing Earth
Our planet is ever-changing, and satellites enable us to observe, record and
analyse that change from a whole new angle. Satellites used to observe our
planet, such as Aqua and Terra, can take images in different colours or visible
light and non-visible radiation. This information can be used to locate new
mineral deposits, study freshwater supplies and the polar ice-caps, find sources
of pollution, monitor bushfires, and even detect the spread of disease in crops
and forests!
Military operations
Satellites can be used for military purposes, including communication, navigation,
weather monitoring, detecting the launch of missiles, as well as spying on military
vehicles and ships.
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School Based Activities
Activity 7: What happened in Victoria?
Aim
Students make comparisons using satellite images to observe changes on the Earth.
Students use scales to assist with their analysis of satellite images.
What you need:
• 6 x colour print-outs of Images 1 & 2 (or image files and software)
• 6 x rulers
What to do:
1. Put students into small groups. Give each group a copy of Image 1. Ask the students to
analyse Image 1.
a. What do they see?
b. What do they think is happening in the image?
c. Can they tell what part of Australia this satellite image has captured?
d. Using the ruler and scale bar, measure how far the smoke has spread.
e. Why might the smoke have spread in that direction?
2. Now hand out Image 2 to each group. Again, ask students to analyse the image.
a. What do they see?
b. How is the image different to the previous image?
c. What damage has the fire done? How can they tell?
d. Using the scale bar, can they work out approximately how much land was
affected?
e. Why might these satellite images be useful to us?
Image 1: 11 January 2007
This image of Victoria’s Great Dividing Range
Mountains was taken on 11 January 2007,
when the Moderate Resolution Imaging
Spectroradiometer (MODIS) on NASA’s Aqua
satellite passed overhead and captured this
image. Places where MODIS detected
actively burning fires are outlined in red. Many
fires were burning dangerously close to Lake
Thomson, the principal source of water for the
City of Melbourne (beyond the western edge of the image).
Image 2: 16 January 2007
Fires that began in early December 2006 were still
raging through the Great Dividing Range Mountains
of eastern Victoria, Australia, on 16 January 2007.
This image of the region was captured by the
Moderate Resolution Imaging Spectroradiometer
(MODIS) on NASA’s Terra satellite just before
11:00 a.m. local time. Places where MODIS
detected actively burning fires are outlined in red.
These images were sourced from:
http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14074
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School Based Activities
Image 1
This image was taken on 11January 2007.
…………………cut prior to handing images to students………..…………
Image 2
This image was taken on 16 January 2007.
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School Based Activities
Activity 8: Cyclone Tracking in Australia
Aim:
Students will be able to use satellite images to predict the pathway of a cyclone.
What you need:
Each student
• A ruler
• Photocopy of Worksheet 4: Cyclone Mapping
Each group
• Either a copy of the satellite images of
Cyclone Monica in colour, or
• Slideshow presentation of Cyclone Monica
(available from:
MuseumVictoria.com.au/Scienceworks/Education/)
What you do:
1. The sequence of satellite images shows the movement of Cyclone Monica
across the Queensland and the Northern Territory in April 2006.
Printout copies of the images (1 print out per group of 6 students) in colour,
alternatively you could use the slideshow presentation.
2. Put students into small groups. Handout (or view) one image at a time. Discuss
the questions on each sheet that relate to the image before moving on to the next
image.
3. Have the students place the cyclone symbol for the first 3 positions of the
cyclone on Worksheet 4: Cyclone Mapping. Next, they connect the symbols
with a dark or coloured line.
4. Next, encourage students to predict where and when the cyclone will hit next.
5. Check IMAGE 4 to see if their prediction was right. Ask the students:
a. Why did we need more than one image to predict the path of the cyclone?
b. What other kinds of events might we want to predict using these kinds of
satellite images?
Background Information:
Cyclone Monica originated in the Coral Sea below the south-eastern tip of Papua New
Guinea. The cyclone moved due west towards the Cape York Peninsula in Queensland,
where it came ashore on the afternoon of April 19 as a Category 3 cyclone. As it crossed
the peninsula, Monica weakened, but when it reached the warm waters of the Gulf of
Carpentaria on the other side, it re-organised and re-intensified to become a Category 5
cyclone. The winds reached speeds of 350 kilometres an hour. When Cyclone Monica
hit the coastline of the Northern Territory, it fortunately missed Darwin, and hit a sparsely
populated area.
Information and images from:
http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=13525
More information about cyclones can be found at:
http://www.bom.gov.au/info/cyclone/#severity
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School Based Activities
Worksheet 4: Cyclone Tracking Chart
Name: ………………………………………………………………..
1. Look at the satellite images of Cyclone Monica.
2. Track its path on this map of Australia by placing the cyclone symbol on the
map.
3. Next to each symbol, write the date.
4. Inside the circle shape, write the category number.
5. Connect the cyclone symbols to show the path of the cyclone.
= cyclone
You can find out more information about Cyclone Monica at:
http://www.bom.gov.au/announcements/sevwx/nt/nttc20060417.shtml
(For use with Cyclone Monica Images 1 to 5.)
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School Based Activities
Activity 9: Geospatial skills and Google Earth
Aim:
To identify features on a satellite image, and to describe the distance, direction and
location of known places.
What you need:
• Photocopy for each student: Worksheet 5: My Google Earth
• Access to a computer room
• Download Google Earth: http://earth.google.com/
What to do:
1. Have students work in pairs.
2. Once they get into Google Earth, allow the students some time to look around.
3. Next, have the students follow the instructions on the Worksheet 5.
4. After the students have followed the instructions, they may like to label other
features in their local area such as the shops, sports fields, or swimming pool.
Extension activities:
Email
The image the students have created can be emailed to themselves or others (perhaps
their parents) by clicking on the envelope symbol, and following the prompts.
Alternatively, the students could print out their page and create the following on their
image: title, scale bar, north point, and legend.
4
Virtual Tour
Students can go on a
virtual tour of the Earth,
and ‘visit’ their
locations. Click on
Tools then click on
Play tour. The tour
should begin.
Students might like to
make place marks for
places on the Earth
where their ancestors
have come from, or
where they or their
parents have travelled
on holidays.
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School Based Activities
Worksheet 5: My Google Earth!
Name: ……………………………………………………………………………………….
Create your own personalised Google Earth!
What to do…
9 Tick this
box when
you have
finished
each task
Find your home on Google Earth.
Place
mark
HOME
SCHOOL
Measure
distance
)
Directions
Copy
image
Place
mark
4
Virtual
tour
Use the Placemark tool:
Create a placemark over your home.
Left click on this icon:
Use your cursor to move the ‘plackmark’ to the position you want.
Next label the ‘pin’ by clicking in the grey box on: Untitled Placemark.
Then type in: MY HOME. Click ok.
Next, find your school. You might need to zoom in or out to find it.
Use the Placemark tool again, and create a placemark above your school.
Left click on the Ruler symbol at the top of the page.
Change the length to ‘metres’.
Hold your cursor over your place mark for your house. Left click.
Move your cursor so as it is over your place mark for your school. Left
click.
How many metres apart are the two locations?……………………………..
Now create a SCALE BAR that is approximately 100 metres long.
To get directions to school from your house.
First left click on your Íplacemark for your home.
A text box should come up that reads:
Directions: To here - From here
Left click on: From here
Next Left click on the Íplacemark for your school.
Again, a text box should come up that reads:
Directions: To here - From here
Left click on: To here
The directions should automatically appear over the satellite image.
Look in the side bar. The distance between the two places should be
shown.
Is this the way you get to school? ……………………………………………..
Is this distance the same as the distance before?……………………………
Left click on: Edit
Left click on: Copy
Left click on: Copy image
Next, open a new Word document.
Next, click on: Paste. Then give your image a title, and date.
Next, save your file using an appropriate file name.
Try making more placemarks on your Google image. You might like to
make placemarks for your friends’ houses, local shops or swimming pool.
You may then like to make placemarks around the Earth for special
locations (such as, where your grandparents might have lived).
You can take a virtual tour of all of the places you have marked on Google
Earth.
First zoom out, so that you are looking at the Earth from space. You can
zoom in and out using the scroll button on your mouse.
Left click on: Tools
Left click on: Play tour
(then it should begin!)
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School Based Activities
How does information from satellites get to Earth?
Activity 10: Bit by bit – the binary system
Name: ………………………………………………………….
Aim
To investigate how information from a satellite gets back to Earth,
and how numbers can represent visual information.
Background information
The information, or data, that a satellite gets from its sensors is stored in the satellite's
computer as numbers. The numbers can be turned into images, which enables
scientists to understand the data. But the data has to be transmitted to Earth and then
turned into an image.
Computer images are made up of millions of tiny dots. Each dot has a number in the data
that tells what colour it should be in the picture. This is done like "paint by numbers" where
a number represents a shade of grey or a colour. If a picture had 8 colours, 1 could be
red, 2 would mean orange, yellow 3, green 4, blue 5, purple 6, white 7, and 8 could stand
for black.
Computers use a number system called binary. Computers use binary because they are
built out of switches (called transistors) that only switch on and off. We use “1” to
represent on, and “0” to represent off. Every number in binary is represented in 1s and 0s.
In a black and white picture; 0 could code for white; 1 could code for black.
Look at this image of the letter "S."
It is made of 25 squares, some black, some white. Starting at
the top left and going across, the first row would be 0 1 1 1 0.
The next row would be 0 1 0 0 0.
Look at the numbers for the rows and see where the 1s and 0s
stand for black and white squares.
Row 1: 0 1 1 1 0
Row 2: 0 1 0 0 0
Row 3: 0 1 1 1 0
Row 4: 0 0 0 1 0
Row 5: 0 1 1 1 0
You can see the "S" shape in the rows.
Log on to the internet and watch the following animation (2 minutes duration) about
how messages are sent from a satellite back to Earth:
http://spaceplace.jpl.nasa.gov/en/kids/st5xband/st5xband.shtml
Then go on to the next page to complete the activities.
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School Based Activities
Activity 10: Bit by bit – the binary system continued…
When data is transmitted from a satellite to the Earth, the numbers are sent as one long
string. If the numbers in the rows are put together, the entire "S" would be:
0111001000011100001001110
This is the data stream. The key is knowing that all these numbers fit in a 5x5 grid of
squares. If you had a grid with more squares, there would be more numbers.
Look at the image of the letter "X" in the grid.
Question 1: Encode each row using 1s for black and 0s
for white.
Row 1: __________________________
Row 2: __________________________
Row 3: __________________________
Row 4: __________________________
Row 5: __________________________
The data stream for X would be:
____________________________________________________
Question 2: Here is a data stream. Create the image that it represents in the grid.
1000101010001000010000100
Hint: write the numbers in the stream in groups of fives to
make the rows of 1s and 0s. Then fill in the squares: black for
1s and white for 0s.
Row 1:___________________
Row 2:___________________
Row 3:___________________
Row 4:___________________
Row 5:___________________
Question 3: Create your own image in the grid, and write out the data stream.
Row 1:___________________
Row 2:___________________
Row 3:___________________
Row 4:___________________
Row 5:___________________
The data stream for this image is:
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School Based Activities
Activity 10: Bit by bit – the binary system continued…
Answers for teachers
Question 1:
The image of the "X" encodes row by row:
Row 1: 1 0 0 0 1
Row 2: 0 1 0 1 0
Row 3: 0 0 1 0 0
Row 4: 0 1 0 1 0
Row 5: 1 0 0 0 1
And the data stream is:
1000101010001000101010001
Question 2:
The data stream in the second part of the activity represents the letter "Y."
Extra information:
Binary numbers can be used to represent any kind of information: pictures, words,
numbers, sounds, etc. Different patterns of 1s and 0s describe different information.
In regular numbers, the number 359 stands for three hundreds, five tens, and nine ones.
In binary, 10000 equals sixteen, 01000 equals eight, 00100 equals four, 00010 equals two,
and 00001 equals one. So 1101 stands for one eight, one four, no twos and one one. 8 +
4 + 1 = 13.
Our black and white pictures only needed one number per dot. For more detailed pictures,
we need more information in each dot of the picture. Longer sequences of ones and
zeroes can tell us the difference between different colours. (00110 could represent red,
while 10100 could represent green.) Just as it was important to know our picture was 5
dots wide and 5 dots tall, it’s important to know how many numbers go with each dot.
Extension:
For more information on binary counting, visit OMSI:
http://www.omsi.edu/visit/tech/binary.cfm
For much more about how computers process information; visit The Journey Inside at Intel
http://www97.intel.com/discover/JourneyInside/TJI_DigitalInfo/default.aspx
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School Based Activities
Investigating the issues of satellite technology
Activity 11: The Great Space Debate
Aim:
To develop students’ understanding of some of the implications and issues relating to
satellite technology and the ways satellites are used.
What you need:
• Photocopies of Worksheet 6: Six thinking hats
What to do:
• Hand out a copy of the worksheet.
• Begin the session by outlining some of the issues surrounding space research and
satellite technology.
• Pose a question to the students to use as their issue question, such as:
o Do the benefits from satellite technology outweigh the negatives?
• Allow students to work in groups to discuss the issues.
• You may like to conduct the session in a computer room or library so students can
research some of the facts. Alternatively, students could be encouraged to bring in
some research about the topic to the class.
• After the students have worked through the Six-hats, discuss the issues as a
group. Ensure that all groups have a chance to be heard, and that their ideas are
listened to non-judgementally by other members of the class.
Background:
Since the launching of Sputnik in 1957, hundreds of satellites now circle our Earth daily.
They provide us with many benefits, such as improved communications, improved weather
reporting, monitoring natural disasters and climate change.
However, with the increasing number and sophistication of satellites, there is an increased
ability to spy on others. You only need to look on Goggle Earth to see how easily you can
locate your house, and the houses of your friends. There were 860 operating satellites
according to a report in New Scientist (8 September 2007), owned by more than 40
countries. The article also suggested that military surveillance satellites may have the
capability to see objects that are just 20 centimetres wide from an altitude of 400 to 500
kilometres.
Operating satellites are not the only things circling our planet - much of what up there is
rubbish – also known as ‘space junk’. Right now there are at least 110,000 pieces of space
junk, bigger than the size of a pea, orbiting Earth. A piece of space junk the size of a pea
might not sound very harmful, but when it is travelling at a speed of 280,000 kilometres per
hour and collides with another object (e.g. the International Space Station) it can have the
same effect as a bullet fired from a gun!
Satellite technology, and the junk it produces, generates many serious issues to consider.
Should anyone be allowed to launch a satellite? Should the number of satellites be
limited? Should we sacrifice our privacy for the benefits of surveillance on other countries
that may pose a threat to us? Who is responsible for all of the space junk created by old
satellites and the launching of satellites? Should they clean it up? What sorts of threats
does it pose?
Finally, do the benefits from satellite technology outweigh the negatives?
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Glossary
Worksheet 6: Six thinking hats
What is your key issue statement or question?
White hat:
List the information, the facts and
figures about the issue.
……………………………….
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Purple hat:
What are your criticisms,
judgements and the
negatives about the issue?
Red hat:
What are your opinions and
feelings
about the issue?
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Yellow hat:
What are the positive
aspects of the issue?
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Green hat:
What are the alternatives or new
ideas relating to the issue?
Blue hat: The overview!
Based on all of the issues and ideas,
what do you think should happen now?
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