NCERT Solutions Class 4 The World Around Us Chapter 10 Our Sky

F R E E S T U D Y M AT E R I A L F O R E V E R Y S T U D E N T

CLASS 4 · THE WORLD AROUND US

NCERT Solutions

Chapter 10: Our Sky

NCERT Textbook — Our Wondrous World

BOOK PAGES SECTIONS QUESTIONS MEDIUM

152 – 163 12 37 English

Solutions, notes, sample papers & more at 29 pages

Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

CLASS 4 · THE WORLD AROUND US · OUR WONDROUS WORLD

NCERT Solutions — Chapter 10: Our Sky
Chapter 10 of Our Wondrous World closes Unit 5, Our Environment — and closes the book. It takes you
outside to look up. You draw the morning, afternoon and night sky, follow the Sun from the East to overhead
to the West, watch your shadow grow long at sunrise and short at noon, join stars into patterns, and keep a
record of the changing shapes of the Moon.

TEXTBOOK BOOK PAGES

Our Wondrous World (Class 4) 152 – 163

SECTIONS QUESTIONS

12 37

MEDIUM

English

Draw — Page 152
Pictures of the Sky

DRAW

Q1 Draw a picture of the sky as it appears in the morning, afternoon and at night, in
the spaces given below.

Morning Sky Afternoon Sky Night Sky

The three spaces printed in the book, waiting for your drawings.

Draw three different skies, one in each box. Colour them fully — do not leave them white.

1. Morning Sky: colour the sky orange and pink. Draw a big orange Sun low down, near the
ground.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

2. Add three or four birds flying out to look for food.
3. Afternoon Sky: colour the sky bright blue. Draw a small yellow Sun high up, above your
head.
4. Add two or three white clouds.
5. Night Sky: colour the sky dark blue or black. Draw the Moon and many small stars.

A correct drawing shows one thing clearly: the sky has a different colour at each time of the day.
Sample answer:

Morning Sky Afternoon Sky Night Sky

A sample set of three skies. Yours may look different.

Why it happens: The Sun lights up our sky. When the Sun is low we see an orange
sky. When the Sun is high we see a blue sky. When the Sun is not in the sky, it is dark
and we see the Moon and the stars.

Try This: Stand at the same window three times in one day and look out. Draw what
you really see. Your night sky may even have clouds and no stars at all.

Write — Page 153

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

Pictures of the Sky

WRITE

Q1 Write down what you observe in the sky during the morning, afternoon and at
night, in the table given below. A few boxes are filled for you. You may expand your
table by adding new points.

MORNING SKY AFTERNOON SKY NIGHT SKY

Orange colour of the sky

Sunlight is strong Moon and stars

Orange Sun

The table as it is printed in the book, with a few boxes already filled.

Fill one point in each empty box. Write only what you can really see in the sky.
Sample answer: the completed table. The four points in black are the ones already printed in
the book.

MORNING SKY AFTERNOON SKY NIGHT SKY

Orange colour of the sky Sky is bright blue Sky is dark

The Sun looks low, near the ground Sunlight is strong Moon and stars

Orange Sun The Sun comes overhead The Moon changes its shape

Shadows are long Shadows are short No sunlight, so no shadows

Birds fly out of their nests Few birds are seen Owls and bats fly about

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Class 4 The World Around Us Chapter 10 Our Sky
a g l AglaSem · NCERT Solutions

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Why it happens: Everything we notice in the sky depends on the Sun. In the

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morning and evening the Sun is low, so the sky looks orange and shadows are long.
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At noon the

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Tip: The book says you may add new points. So add a row of your own — “kites in
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the sky”, “aeroplane leaving a white line”,
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Q2 Share your observations with your classmates and compare them.

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Do this in small groups of four or five.

1. Read out your table, one column at a time.

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2. Listen to your friends and put a tick next to every point that is the same as yours.
3. Write any new point you like in yourem
a s own table, using a coloured pencil.

agl and how many were new.
4. Count how many points matched

What you will find: most of the points match, because all of you looked at the same sky. The

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points that do not match are usually about time and place — one friend woke up earlier,

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another looked out from a roof.
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m sky’ — he gets up at five o’clock. Kamla’s night sky had no stars, because it was cloudy in
Sample answer: “Five of us wrote ‘orange sky’ for the morning. Only Ravi wrote ‘a thin Moon still

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Why we compare: Comparing shows that the sky is the same for everybody, but
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what you notice depends on when you look and how carefully you look.

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Have you observed any change in the activities, and the behaviour of animals and
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Q3

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plants at different times of a day? Discuss these changes with your friends and
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Yes. Animals and plants change what they do as the day goes on.

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Sample answer: a list made after watching for one full day.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

TIME OF ANIMALS AND BIRDS PLANTS
DAY

Early The cock crows. Birds chirp and fly out of their nests. Many flowers open. Drops of dew sit
morning Cows and goats are taken out to graze. on the leaves.

Noon Dogs and buffaloes rest in the shade. Very few birds are Leaves droop a little in the strong
seen. sunlight.

Evening Birds fly back to their nests. Cows come home. Insects Many day flowers close up.
start to buzz around the lamp.

Night Owls, bats, crickets and mosquitoes come out. Most Night flowers like raat ki rani open
animals sleep. and give a strong smell.

Why it happens: Most animals move about when there is light and food, and rest
when it is dark. Some animals do the opposite — owls and bats come out at night.
Plants work with sunlight, so many of them open in the morning and close in the
evening.

Tip: Watch one animal near your home for a week — a crow, a street dog or an ant
line. Write one line about it each morning and each evening. The pattern will be easy
to see.

Q4 Can you guess the brightest object in the sky?

The Sun. It is the brightest object in our sky.

It is so bright that the other stars cannot be seen when it is in the sky.
It gives us both light and heat.

Why the stars hide: The stars are still up there in the daytime. The Sun’s light is
simply so strong that our eyes cannot pick out their small twinkles. After sunset the
strong light goes, and the stars appear again.

Check it yourself: Look at a lighted torch bulb in a dark room — you see it at once.
Switch on the tube light and look again. The torch is still on, but it is hard to notice.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

Discuss — Page 154
Sunrise and Sunset

DISCUSS

Q1 When the Sun rises: How does the sky look?

The dark sky slowly becomes light.

The part of the sky where the Sun comes up turns orange, pink and golden.
The Sun itself looks orange and sits low, near the ground.
The stars and the Moon fade away and are no longer seen.
Bit by bit the whole sky turns pale blue.

Why it happens: The Sun is the brightest object in the sky. As it appears, its light fills
the sky, and the weaker light of the stars can no longer be seen.

Q2 When the Sun rises: What do the birds and animals do?

They wake up and become busy.

The cock crows. Birds chirp loudly and fly out of their nests to look for food.
Cows, goats and buffaloes are let out and taken to graze.
Butterflies and bees come to the open flowers.
Owls and bats, which were out all night, go back to rest.

Why it happens: Most animals find their food in the light. So their day begins when
the Sun’s light comes back.

Q3 When the Sun rises: What changes do we find at home?

The home wakes up with the Sun.

The lights are switched off — sunlight now comes in through the windows.
Everyone gets up, brushes and bathes.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

Tea is made and breakfast is cooked. The smell of food fills the house.
Clothes are put out in the Sun to dry.
Children get ready for school and elders leave for work.

Why it happens: Sunlight is free light and free heat. So we do most of our work,
drying and cooking while it is there.

Q4 When the Sun sets: How does the sky look?

The bright sky slowly becomes dark.

The part of the sky where the Sun goes down turns orange and red.
The Sun looks big and orange and slips down on the other side of the sky.
The colours fade, and the sky turns grey and then dark.
One by one the stars and the Moon begin to appear.

Why it happens: The Sun’s strong light is going away. As it goes, the small lights of
the stars are no longer hidden, so we start to see them.

Q5 When the Sun sets: What do the birds and animals do?

They come back and settle down for the night.

Birds fly back to their nests in rows, calling to one another.
Cows and goats return home from the fields.
Hens go into their coop and most animals lie down to sleep.
Owls, bats, crickets and mosquitoes come out — their day is just beginning.

Why it happens: Animals that hunt and feed by daylight must be safe before the
dark. A few animals, like owls and bats, can move about in the dark, so they come
out then.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

Q6 When the Sun sets: What changes do we find at home?

The home gets ready for the night.

The lights and lamps are switched on, because sunlight is gone.
Children come in from play and wash their hands and feet.
Clothes that were drying are taken in.
Dinner is cooked and the family sits together to eat.
Homework is done, doors are shut, and everyone goes to sleep.

Why it happens: Once the Sun sets there is no free light or heat. So we make our
own light and do the quiet, indoor part of the day.

Tip: Ask an elder at home what changes they notice at sunrise and sunset. Older
people often remember what the sky, the birds and the village sounded like before
there were electric lights.

The Shadows — Page 155
Interesting things about shadows

Q1 Have you ever noticed your shadow moving along with you?

Yes. The shadow goes wherever you go.

If you walk, the shadow walks. If you run, the shadow runs with you.
If you make different poses, the shape of the shadow changes in the same way.
If you jump, the shadow jumps too.

Why it happens: A shadow is made where your body blocks the light. Your body is
always in the same place as you, so the dark patch it makes has to move with you as
well.

Try This: Stand in the Sun and put your hands on your head like two horns. Look at
the ground. The shadow has horns too.

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Class 4 The World Around Us Chapter 10 Our Sky
a g l AglaSem · NCERT Solutions

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In the pictures above, what are the differences in the shadows?
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Q2

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Early morning shadow Noon shadow Evening shadow

The three pictures printed on page 155, redrawn simply.

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ANSWER co
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The shadows

Morning: the shadow is long.

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Noon: the shadow is short — it lies almost under the feet.
Evening: the shadow is long again.
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But the evening shadow falls in the opposite direction to the morning shadow.

So the pattern is: long → short → long, and the two long ones point opposite ways.

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Why it happens: The Sun appears low in the sky in the morning and m in the evening,
com makes long shadows. At noon it is overhead, so the a
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as the other side in the evening, the shadow turns right round.
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Q3 How does my shadow change?

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Early morning shadow Noon shadow Evening shadow

The three pictures printed on page 155, redrawn simply.
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ANSWER a
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Your shadow changes in three ways.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

1. Its length changes. It is long in the early morning, short at noon, and long again in the
evening.
2. Its direction changes. The evening shadow points the opposite way to the morning shadow.
3. Its shape changes whenever you change your pose — spread your arms and the shadow
spreads its arms.

Why it happens: The Sun appears to move across the sky through the day. Since the
light comes from a new place every hour, the dark patch you make on the ground
has a new length and a new direction every hour.

Q4 Does this happen to all the objects?

Early morning shadow Noon shadow Evening shadow

The three pictures printed on page 155, redrawn simply.

Yes. It happens to every object that blocks the light.

A tree, a pole, a wall, a bucket, a bicycle — each one makes a shadow.
Every one of those shadows is long in the morning, short at noon and long again in the
evening.
Page 158 of your book shows exactly this for a tree: three pictures, three different shadows.

Why it happens: The rule does not belong to you — it belongs to the light. The
same Sun lights up everything around you, so every object’s shadow changes
together, in the same way, at the same time.

Check it yourself: At noon, look at the shadow of a pole and the shadow of a friend
at the same moment. Both are short. Come back in the evening. Both are long.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

Q5 Are shadows formed only in the sunlight?

No. Any light can make a shadow, not only sunlight.

A torch makes a shadow — you will see this in the activity on page 156.
A lamp, a candle, a tube light and even a mobile phone screen make shadows.
Moonlight on a bright full-Moon night can also make a faint shadow.

Why it happens: A shadow only needs two things — a light, and something that
blocks the light. It does not matter whether the light comes from the Sun or from a
torch.

Try This: Close the door of a dark room, switch on a torch, and hold your hand in
front of it. A shadow appears on the wall at once.

Q6 I wonder why these changes occur?

The changes happen because the Sun appears to move across the sky.

1. In the morning the Sun appears in the East, low down.
2. By noon it has come overhead.
3. In the afternoon it moves towards the West and goes low again.

So the light reaches you from a different side at every hour. The shadow always falls on the side
away from the light — so it turns as the Sun turns, and it stretches when the Sun is low.

Why it happens: Your book puts it in one line on page 157: “The direction of the
shadow also changes because of the movement of the Sun.”

Find out — Page 156

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

The Shadows

FIND OUT

Q1 Take a torch and a stick. Close the doors and windows to make the room dark. Hold
the stick in one place and turn on the torch. Shine the torchlight on the stick.
Observe the changes in the shadow of the stick, in the following situations: (a)
Move the stick back and forth. (b) Change the direction of the torch.

What you need: a torch, a straight stick or a pencil, and a dark room with a plain wall.

1. Shut the doors and windows so that the room is dark.
2. Stand the stick up, or ask a friend to hold it still about one metre from the wall.
3. Switch on the torch and shine it on the stick. A dark shadow of the stick appears on the wall.
4. (a) Keep the torch still and move the stick towards the torch, then away from it. Watch the
shadow each time.
5. (b) Keep the stick still and move the torch — to the left, to the right, higher, lower. Watch the
shadow each time.

What you will see:

Stick nearer the torch → the shadow becomes bigger. Stick further from the torch → the
shadow becomes smaller.
Torch moved to the left → the shadow swings to the right, and the other way round.

Sample answer: “When I brought the pencil close to the torch, its shadow grew till it covered
half the wall. When I moved the torch to my left, the shadow slid to the right side of the wall.”

wall wall

Torch near the stick Torch far from the stick
Bigger shadow Smaller shadow

The same stick, the same wall, only the torch is moved.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

Why it happens: The shadow is the dark space behind the object where the light
cannot reach. Bring the object near the light and it blocks more light, so the dark
space is bigger. Move the light to a new side and the dark space moves to the
opposite side.

Tip: This is the same rule as sunlight — only here you are moving the light, while
outside it is the Sun that appears to move.

Q2 If we change the distance of the source of light from the stick (an object), how will
the shadow change?

The size of the shadow changes.

If the object is close to the source of light, the shadow is bigger.
If the object is far from the source of light, the shadow is smaller.

wall wall

Torch near the stick Torch far from the stick
Bigger shadow Smaller shadow

The same stick, the same wall, only the torch is moved.

Why it happens: Light spreads out as it travels. An object held close to the torch
stands in the narrow part of the light and blocks a large share of it, so it throws a big
shadow. The same object held far away blocks only a small share, so the shadow
shrinks.

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Class 4 The World Around Us Chapter 10 Our Sky
a g l AglaSem · NCERT Solutions

co m
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Check it yourself: Hold your hand close to a lamp and look at the wall — a huge

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hand. Step back and the hand becomes small again.

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Q3 If we change the direction of the torch (source of light), how will the shadow

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change?

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The direction of the shadow changes.

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Shine the torch from the left → the shadow falls to the right.

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Shine the torch from the right → the shadow falls to the left.
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g below the stick.
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Hold the

a e in one line: the shadow always falls on the side away from the light.
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Why it happens: Light travels in straight lines. The stick stops that light, and the
dark space is left straight behind the .stick.
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new side, “behind the stick” means

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We observe that shadows in the morning and evening form in m
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Because the Sun is on a different side of the sky at those two times.
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1. In the morning the Sun appears in the a
West.
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2. In the evening the Sun has
the East.

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That is why the evening shadow points exactly opposite to the morning shadow.
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the torch, and it appears to move from the East to the West through the day.
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Draw — Page 157 a

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

Position of the Sun and shadows

DRAW

Q1 Draw the position of the Sun and corresponding shadows in the images given
below.

Morning Noon Evening

The three pictures printed in the book. The Sun and the shadows are missing.

Draw two things in each picture: where the Sun is, and where the shadow falls.

1. Morning: draw the Sun low down on one side. Draw a long shadow on the ground, on the
other side of the child.
2. Noon: draw the Sun right at the top, above the child’s head. Draw a short shadow just under
the feet.
3. Evening: draw the Sun low down on the opposite side from the morning. Draw a long
shadow again, pointing the other way.

Sample answer:

East West

Morning Noon Evening

The same three pictures with the Sun and the shadow drawn in.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

The rule your drawing must follow: the shadow always falls on the side away from the Sun.

Why it happens: The Sun appears to move from the East to overhead till noon, and
then gradually moves towards the West in the afternoon. The direction of the
shadow changes because of this movement of the Sun.

Tip: Your book’s own tree pictures on page 158 are drawn the same way — Sun on
the left in the morning with the shadow to the right, Sun on top at noon, Sun on the
right in the evening with the shadow to the left.

Play with Shadows — Page 158
Shadow formation by the Sun

ACTIVITY

Q1 It is fun to make different shapes with shadows. Try it with your friends!

Make hand shadows on a wall. Here is how.

1. Choose a room with a plain light-coloured wall. Shut the doors and windows.
2. Switch on one torch or lamp and point it at the wall.
3. Stand between the light and the wall. Hold your hands in the beam of light.
4. Fold your fingers into different shapes and watch the wall, not your hands.
5. Move your hands nearer the light and the shadow grows bigger.

Sample answer — easy shapes to start with:

Bird: cross your two hands at the wrists and flap your fingers like wings.
Dog: join your fingers to make a long face; let the thumb open and shut as the mouth.
Deer: spread the fingers of one hand behind the fist of the other for the horns.
Snake: hold one hand flat and let it wave slowly.

What the play teaches you: the shadow takes the shape of the thing that blocks the light — not
its colour. A red hand and a brown hand make exactly the same black shadow.

Why it happens: Light travels in straight lines. Wherever your hand stops it, no light
lands on the wall, and that dark patch has the same outline as your hand.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

Did you know? Shadow puppetry has been practised in India for a long time. You
can cut out a peacock or an elephant from thick paper, tape it to a stick, and put on a
shadow play for your class. Shadows can also tell the time — ancient people made a
device called a sundial. Raja Jai Singh of Jaipur built Jantar Mantar in Jaipur, Ujjain,
Delhi, Varanasi and Mathura, and its sundial, the Samrat Yantra, tells time accurately
from a shadow.

Night Sky — Page 159
Patterns of stars

DRAW

Q1 Draw any pattern you have observed, in the box below:

The empty box printed in the book.

You must look at the real night sky first. Then draw what you saw.

1. Go out about an hour after sunset, with an elder. Choose an open place away from bright
lights.
2. Wait for five minutes so that your eyes get used to the dark. Many more stars will appear.
3. Look for a group of bright stars that seem to make a shape.
4. Mark each bright star as a dot in the box. Keep the dots in the same places as in the sky.
5. Join the dots with light pencil lines. Give your pattern a name.

Sample answer: a well-known pattern of seven bright stars. In India it is called Saptarshi, the
Seven Sages.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

A sample star pattern: seven bright stars joined by lines.

Why we see patterns: The stars do not really touch one another. Our eyes simply
join bright dots that lie near each other, the way we see shapes in clouds. That is why
the same seven stars have been given different names by different people.

Tip: Your pattern does not have to be Saptarshi, and it does not have to match your
friend’s. Any group of stars you noticed yourself is a correct answer. The point of the
activity is to make you look up.

Q2 Share the drawing with your friends and discuss the common patterns of stars.

Do this in class the next morning.

1. Pin all the drawings on one wall or lay them on a table.
2. Look for drawings that show the same group of stars. Put them together.
3. Ask each friend what they named their pattern.
4. Make one class list: pattern, who saw it, and the names given to it.

What you will find: a few patterns come up again and again, because everybody was looking at
the same sky. The group of seven bright stars is usually drawn by many children. But the names
differ — one child calls it a pot, another a kite, another Saptarshi.
Sample answer: “Seven of us drew the same seven bright stars. Asha called it ‘the big spoon’.
Iqbal called it ‘the plough’. My grandmother calls it Saptarshi.”

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Class 4 The World Around Us Chapter 10 Our Sky
a g l AglaSem · NCERT Solutions

co m
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Why this is worth doing: Sharing shows that the sky is the same for everyone in

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your town, but the shape you see in it is your own idea. Both are true at once.

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Draw — Page 160
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Shapes of the Moon

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DRAW
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Q1 Observe the Moon in the sky and draw the shapes of the Moon you have observed
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on different nights.

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The nine empty boxes printed in the book.
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This is a watching job. Keep a Moon diary for about two weeks.
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m a s emevery night.
1. Pick one time — say eight o’clock at night — and go out at that time
o the Moon. Write the date in a corner of the box. agl
2..cFind

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4. Use one box for each night. If clouds hide the Moon, write “cloudy” and use the next box.
5. Keep going till you have filled all nine boxes.
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What your nine boxes will show: the shape changes a little every night, and it changes in order agl
— never by jumping about.
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Sample answer: a

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

Not visible Thin ‘C’ Half Almost full Full round Almost full Half Thin ‘C’
(Amavasya) (Poornima)

and then Amavasya again

The order in which the Moon’s shape changes, night after night.

A night when the Moon is a complete circle is Poornima, the full Moon.
A night when the Moon is not visible at all is Amavasya, the new Moon.
In between you will see the ‘C’ shape and the half shape, as if the Moon has been cut down
the middle.

Why this is worth doing: Ancient people did exactly this. They used the shape of the
Moon to keep count of the days, and that gave rise to the earliest calendars.

Tip: Look on a few nights soon after sunset and on a few nights later. On some days
the Moon rises late, so you may have to wait. A cloudy night is not a failed night —
write it down and carry on.

Discuss — Page 160
Shapes of the Moon

DISCUSS

Q1 Is there a pattern to the way the shape of the Moon changes?

Yes, there is. The shape changes in a fixed order, and then the order repeats.

1. A night with no Moon at all — Amavasya.
2. Then a thin shape like the letter ‘C’.
3. Then it looks as if it has been cut down the middle.
4. Then almost round, and then a complete circle — Poornima.
5. After that it gets thinner again, night by night, till there is no Moon once more.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

Not visible Thin ‘C’ Half Almost full Full round Almost full Half Thin ‘C’
(Amavasya) (Poornima)

and then Amavasya again

The order in which the Moon’s shape changes, night after night.

So the pattern is: thin → half → full → half → thin → not visible → and it all begins again.

Why this matters: Because the pattern repeats in the same way every time, people
could count days with it. That is how the earliest calendars began, long before clocks
and printed calendars.

Check it yourself: Look at an Indian calendar at home. Poornima and Amavasya are
marked on it, and they come back again and again, with the same number of days in
between.

Q2 Are there days when the Moon is not visible in the sky?

Yes. There are nights when the Moon is not visible at all.

Such a night is called Amavasya, or the new Moon.
It happens periodically — that is, it comes back again after the same number of days, every
time.
Diwali is celebrated on the day when there is no Moon in the sky. That is why we light so
many lamps.
Eid is celebrated on the day the Moon is seen on the first night after a New Moon.

Why we should be careful: A cloudy night is not Amavasya. On a cloudy night the
Moon is there but hidden behind the clouds. On Amavasya the sky may be perfectly
clear and there is still no Moon.

Write — Page 162

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

Festivals of the Sun and the Moon

WRITE

Q1 Do you celebrate any festivals in your family or community related to the Sun or the
Moon? What do you call them in your language?

Find out first, then write. This answer must be your own family’s.

1. Ask your mother, father or grandparents which festivals at home depend on the Sun or the
Moon.
2. Ask two questions about each one — What do we call it in our language? and Is it on a full-
Moon day, a no-Moon day, or a Sun day?
3. Write the name in your own language first, then in English.

Sample answer:

FESTIVAL SUN OR MOON NAMES USED IN DIFFERENT
PLACES

Makar Sankranti Sun Pongal, Magh Bihu, Uttarayan, Lohri

Chhath Puja Sun Chhathi Maiya, Surya Shashthi

Diwali Moon — no Moon in the sky Deepavali, Deepawali

Karva Chauth Moon Karwa Chauth

Rakshabandhan Moon — full Moon Rakhi, Nariyal Poornima

Guru Poornima, Buddha Moon — full Moon Poornima, Purnima
Poornima

Eid Moon — first night after a New Eid-ul-Fitr, Chand Raat
Moon

Why so many festivals follow the sky: Long before there were printed calendars,
people fixed their dates by what they could see — the shape of the Moon and the
journey of the Sun. Many of those dates are still kept today.

Tip: Write each festival name in your own script as well as in English. Pongal and
पोंगल name the very same day.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

Let us reflect — Pages 162–163
End-of-chapter questions

LET US REFLECT

Q1 Give two differences between: (a) Day and night

Two differences between day and night:

1. In the day the Sun is in the sky and everything is bright. At night the Sun is not in the sky
and it is dark.
2. In the day we see the Sun and the blue sky. At night we see the Moon and the stars.

(You may also say: there are shadows in the sunlight during the day, and no sunlight shadows at
night.)

Why: Everything that is different between day and night follows from one fact — the
Sun’s light is there, or it is not.

Q2 Give two differences between: (b) Sky in the morning and in the evening

Two differences between the morning sky and the evening sky:

1. In the morning the sky turns orange on the East side, where the Sun appears. In the
evening it turns orange on the West side, where the Sun goes down.
2. The morning sky is getting brighter — the stars fade away. The evening sky is getting
darker — the stars begin to appear.

Why: Both skies look orange because the Sun is low at both times. What tells them
apart is the side of the sky and which way the light is going — up in the morning,
down in the evening.

Q3 Give two differences between: (c) Our activities during the day and at night

Two differences in what we do:

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Class 4 The World Around Us Chapter 10 Our Sky
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1. During the day we go to school, work, play outside and dry our clothes in the Sun. At night
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a s em Enquire about something — A teacher said that the Sun appears to move from East
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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

What makes these good questions: Each one takes the teacher’s sentence and
asks for the next step — really or only in appearance?, every day or not?, and what
about the night? Your teacher will explain the reason for this apparent journey in a
higher class.

Tip: Write your questions down before you ask them. A question written down is
almost always sharper than one asked in a hurry.

Q6 Figure it out — Suppose you stand at the same spot during the morning and the
afternoon. In the morning, your shadow points in one direction, while in the
afternoon it points in another. Why? Would the length of your shadow be the same
at both times?

Why the direction changes: because the Sun is on a different side of the sky at the two times.

1. In the morning the Sun appears in the East. Your shadow falls away from it, on the West
side.
2. By the afternoon the Sun has moved towards the West. Now your shadow falls the other
way, on the East side.

You did not move at all. The Sun moved, so the shadow moved.

West
East

Morning Afternoon
The same child, the same spot, two different times of the day.

Would the length be the same? No.

Early in the morning the Sun is low, so your shadow is long.
Near noon the Sun is overhead, so your shadow is at its shortest.
Later in the afternoon the Sun goes low again and the shadow grows long once more.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

So the two shadows are different in direction, and usually different in length as well.

Why it happens: A shadow always falls on the side away from the light, and it
stretches out when the light comes from low down. Both facts come from the same
journey of the Sun — East, overhead, West.

Check it yourself: Stand on the same tile in the school ground at 8 o’clock and again
at 12 o’clock. Mark the tip of your shadow with a stone each time, and then compare
the two stones.

Q7 Get creative with words — Write your own poem inspired by the beauty of the sky.

Write four to eight lines. Here is an easy way to build them.

1. Pick one thing in the sky — the Sun, the Moon, a star, a cloud or a rainbow.
2. Write one line saying what it looks like. Compare it to something you know: a laddoo, a lamp,
a boat, cotton wool.
3. Write one line saying what it does — it rises, it hides, it twinkles, it floats.
4. Make the last word of the second line rhyme with the last word of the first, if you can.
5. Give the poem a title.

Sample answer:

My Sky

The morning Sun is a big orange ball,

It climbs up slowly, over the wall.

At noon it is white and straight up high,

My little shadow has nowhere to lie.

At night the Moon is a slice of lime,

The stars come out and keep the time.

What makes it a poem: Each line says one small, true thing that you have really
seen. The rhyme only helps you remember it — it is the picture in the line that
matters.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

Tip: Write your poem in the language you think in. A poem in Hindi, Tamil or
Bhojpuri about the sky is just as good.

Q8 Get creative with words — Complete the riddle below and answer it — “Only one
colour, but not one size / Appears with light, looks very nice / ____________ / ____________”
What is it?

The answer to the riddle is a shadow.
Now the two missing lines. They should add one more clue and keep the rhyme.
Sample answer — the completed riddle:

Only one colour, but not one size

Appears with light, looks very nice

It runs beside me but makes no sound,

It lies on the wall or flat on the ground.

What is it? → A shadow

Another pair of lines that works just as well:

Long in the morning and short at noon,

It hides from me in the dark, very soon.

How each clue fits a shadow:

Only one colour — every shadow is dark, whatever colour the object is.
But not one size — it is long in the morning, short at noon, long again in the evening.
Appears with light — no light, no shadow.

Why the answer must be a shadow: Nothing else in this chapter is always the
same colour, always changing size, and only there when a light is there. The Sun, the
Moon and the stars are all bright, not dark.

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Class 4 The World Around Us Chapter 10 Our Sky AglaSem · NCERT Solutions

Chapter at a glance
The sky looks different at different times of the day. The colour of the sky changes in the
morning, afternoon and at night. Even the Sun’s colour appears to change. The activities of
birds, animals, trees and humans change too.
The Sun is the brightest object in the sky. It is so bright that other stars cannot be seen
when it is in the sky. It gives us light and heat. It appears to rise, move up till it is overhead,
and then go down on the other side.
Shadows change through the day. Morning shadows are long, noon shadows are short
and evening shadows are long again. Evening shadows fall in the opposite direction to
morning shadows.
A shadow follows the light. If the object is close to the source of light, the shadow is
bigger. If the direction of the light changes, the direction of the shadow changes too. The
Sun appears to move from the East to overhead at noon and then towards the West, so the
shadow turns as the day goes on.
Shadows can tell the time. Ancient people made a device called a sundial. Raja Jai Singh of
Jaipur built Jantar Mantar in Jaipur, Ujjain, Delhi, Varanasi and Mathura. Its sundial is called
Samrat Yantra.
The night sky has thousands of twinkling stars and we see them in patterns. The Moon
appears to be the biggest object in the night sky, and its shape looks different on different
nights.
Poornima and Amavasya. A complete round Moon is Poornima, the full Moon. A night with
no Moon at all is Amavasya, the new Moon. Ancient people counted days by the Moon’s
shape, and that gave us the earliest calendars. Diwali falls on a no-Moon night;
Rakshabandhan, Guru Poornima and Buddha Poornima fall on a full-Moon night; Eid is on
the day the Moon is seen on the first night after a New Moon.
India has been to the Moon. On 23 August 2023, India’s Vikram Lander landed on the
Moon and collected data about the Moon’s surface.

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Class 4 The World Around Us Chapter 10 Our Sky
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Quick revision
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WORD CHAPTER PAGE

Sunagl The brightest object in our sky; it Other stars cannot be seen while the Sun is in 153
gives us light and heat the sky

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Sunrise The time when the Sun appears in
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The sky turns orange and birds fly out of their 154
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the morning
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Sunset The time when the Sun goes
a Birds return, lamps are lit and stars begin to 154

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Shadow The dark shape made when an Your shadow runs with you and changes 155

. you change your pose

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Morning A long shadow, made when the
Sun is low
The first of the three shadow pictures 155

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Noon shadow A short shadow, made when the The second of the three shadow pictures 155
Sun is overhead
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East and West a
The side the Sun appears from, The Sun appears to move from the East to 157
and the side it goes down overhead to the West

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Sundial A device that tells the time from a Samrat Yantra at Jantar Mantar, built by Raja Jai 158

co m shadow Singh of Jaipur
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Pattern A shape we see when we join You draw a pattern you have seen and compare 159

ag stars bright stars in the night sky it with your friends’

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Poornima The night when the Moon is a Rakshabandhan, Guru Poornima and Buddha 160

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Amavasya The night when the Moon is not Diwali is celebrated on the day when there is no 161
visible at all Moon in the sky

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The Vikram Lander landed on 23 August 2023 162
India’s mission to the Moon

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and collected data

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