NCERT Solutions Class 6 Science Chapter 12 Beyond Earth

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 6 · SCIENCE

NCERT Solutions

Chapter 12: Beyond Earth

NCERT Textbook — Curiosity

BOOK PAGES SECTIONS QUESTIONS MEDIUM

231 – 252 12 36 English

Solutions, notes, sample papers & more at 42 pages

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

CLASS 6 · SCIENCE · CURIOSITY

NCERT Solutions — Chapter 12: Beyond Earth
Complete NCERT Solutions for Class 6 Science Chapter 12 Beyond Earth from the NCERT textbook Curiosity.
Every question of the chapter is solved — Activities 12.1 to 12.4, all the in-text questions from pages 232 to
247, and the full Let us enhance our learning (pages 249–251) and Learning further (pages 251–252)
exercises — with labelled star charts of the Saptarishi and Orion, the correct order of the eight planets and
diagrams you can copy into your notebook.

TEXTBOOK BOOK PAGES

Curiosity (Class 6) 231 – 252

SECTIONS QUESTIONS

12 36

MEDIUM

English

In-text Questions — Page 232
Chapter opening — Yangdol and Dorjay watch the night sky in Nubra, Ladakh

Q1 Have you ever looked at the stars in the night sky and tried to connect them with
imaginary lines, just like dots and lines in a drawing?

Yes — and that is exactly how people all over the world made the constellations. On a clear,
dark night the stars look like bright dots scattered on a black sheet. If you join a few of the
brightest dots with imaginary lines, a shape jumps out at you.

Seven bright stars in the northern sky join up into a giant ladle or cooking spoon. Indians call
it Saptaṛiṣhi; in English it is the Big Dipper.
Three stars in a short, straight, evenly-spaced line in the winter sky form the belt of the
hunter Orion.
A small, hazy cluster looks like a tiny bunch of grapes — the Kṛittikā (Pleiades).

Why our mind does this: the human brain is very good at spotting patterns. Given a
random scatter of dots, it keeps trying to fit a familiar shape on to them. The lines
are not really in the sky and the stars in a pattern may be at completely different
distances from us — they only look close together because they lie in the same
direction.

Page 1 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Try This: On the next moonless night, go up to a terrace with an elder, look towards
the north and find the ladle shape of the Saptaṛiṣhi. Sketch it in your notebook with
a pencil — you have just made your first star map.

Activity 12.1: Let us draw — Page 232

Page 2 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

12.1 Stars and Constellations — Fig. 12.2 A part of the night sky

ACTIVITY

Page 3 of 42

as e
Class 6 Science Chapter 12 Beyond Earth
a g l AglaSem · NCERT Solutions

co m
m.
Fig. 12.2 shows bright stars in one part of the night sky. Look at it carefully and try
se
Q1

o m l a
to imagine a pattern formed by a group of stars. Draw lines to connect the stars
g to the pattern
m .c the pattern. Think of an animal or an object that isasimilar
and make

l a se by you. Write its name near your pattern. Repeat the above steps and make
drawn
a g some more patterns. Now think of an interesting story about your patterns.

co m
e m . ag
g l as
a

co m
e m.
m l as
m .co a g
l a se
a g
m a s
m .co agl
l a se
a g

co m
m .
m as e
.co a g l
se m
g l a
a
se m
com g l a
m . a
ase
agl

co m
m .
m ase
.co a g l
se m
g l a
a c
.
Fig. 12.2, page 232 — a part of the night sky. Each dot is a star; the bigger the dot, the
brighter the star.
s e m
m a
e m . co agl
g l as
ANSWER a
m
How to do it: take a pencil, put a light dot on every bright star in Fig. 12.2 (ignore the faint

. co
em
m l as
.co a g
Page 4 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

ones), and then join four to eight of those dots with straight lines. Do not try to join every star —
a good pattern uses only a few.

1. Pick the brightest stars first. They are the ones you would actually notice in the sky.
2. Join them with straight, simple lines — a square, a triangle, a hook, a chain.
3. Ask yourself: what does this shape remind me of? Write that name beside it.
4. Now repeat on a different group of stars in the same figure.

Sample answer: here are four patterns a student made from the same figure, with the story
that goes with each.

SHAPE YOU DRAW NAME YOU THE STORY
GIVE IT

Four stars in a rectangle, Grandmother's Three thieves are quietly dragging away the cot on
with three more trailing cot which grandmother is sleeping. She never wakes up, so
off one corner they must circle the sky with it every night.

A long curved chain of Peacock's tail A peacock spread its tail so wide during a monsoon
five stars dance that the feathers stuck in the sky.

A triangle with a short tail Kite (patang) A boy's kite snapped on Makar Sankranti and flew so
high that it never came down.

Three stars in a row with Bullock cart A farmer's cart carrying grain to the market — the three
two above and two below stars in the middle are the yoke.

Why there is no single correct answer: the lines are imaginary. Nothing in the sky
joins the stars. Every group of people who looked up drew different lines and told
different stories — and every one of them is a valid answer to this activity.

Did you know? The very same seven stars are the Saptaṛiṣhi (seven sages) in India,
the Great Bear in Europe, the Plough in Britain and a boat to fishermen on the
Konkan coast.

Q2 Compare your patterns with the patterns drawn by your friends. Are the patterns
same or different? Narrate your story to others and listen to their stories. Do you
notice that everyone's patterns, names and stories are different? Is it not fun?

The patterns are almost always different — and that is the whole point of the activity.

Two friends may pick different stars to join out of the same field of dots.

Page 5 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Even when they pick the same stars, they may join them in a different order and get a
different shape.
And even when the shape is the same, the name depends on what that student sees around
them every day — a cot, a kite, a boat, a bullock cart, a cricket bat.

Why this happens: the pattern is made by our imagination, not by the sky. So it
takes its shape from the life of the person imagining it. Fishermen see a boat;
farmers see a plough or a cart; hunters see a hunter. This is exactly why the same
seven stars have dozens of names across the world.

Check it yourself: ask five classmates to show you their drawings without telling
you the name first. Can you guess what each one is? If you cannot, that proves how
personal these patterns are.

In-text Questions — Pages 233 & 235
12.1 Stars and Constellations — use of star patterns, and how to spot them

Q1 Do we find patterns among the stars just for fun or is there some use of these
patterns?

Both — but the use came first. Star patterns were a serious, practical tool long before they
were entertainment.

Finding directions. Before the magnetic compass, and long before GPS, sailors and
travellers steered by the stars. The Big Dipper leads you to the Pole Star, which stands
almost fixed in the north. Caravans crossing Nubra in Ladakh used exactly this trick. It is still
kept as a backup method in emergencies.
Recognising stars. Thousands of stars look alike. Grouping them into shapes makes it
possible to point at one and say which star it is — "the bright one at the bottom-right of
Orion".
Keeping a calendar. Different constellations rise in different seasons, so their appearance
told people when to sow, when to harvest and when a festival was due.
Storytelling and culture. Each pattern carried a story, and the story helped children
remember the pattern.

Page 6 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Why the Pole Star works as a direction-finder: it lies almost exactly above the
Earth's North Pole, along the line of the Earth's axis. As the Earth spins, every other
star seems to wheel across the sky, but the Pole Star hardly moves. Face it, and you
are facing north.

Did you know? In the early twentieth century the International Astronomical
Union (IAU) fixed agreed boundaries and listed 88 constellations, dividing the
entire sky into 88 regions. So today a constellation is a region of the sky, not just a
pattern of stars.

Q2 How can we identify some of these constellations in the night sky?

Learn one landmark pattern first, then hop from it to the others. That is how every sky-
watcher begins.

1. Know the shape before you go out. Study Fig. 12.3 and Fig. 12.4, or print them, so the
shape is already in your head.
2. Know where and when to look. Not every constellation is visible from every place on every
night. The Big Dipper is best seen towards the north at about 9 p.m. in summer; Orion is
best seen in India from December to April, after sunset.
3. Start with the easiest. The three evenly spaced stars of Orion's belt and the ladle of the Big
Dipper are unmistakable.
4. Star-hop. Big Dipper → Pole Star (5× the gap between the two pointer stars). Orion's belt →
extend the line eastwards → Sirius, the brightest star in the night sky.
5. Use a sky-map app such as Sky Map or Stellarium on a mobile phone to confirm what you
are looking at.

Tip: choose a dark, open place away from street lights and tall buildings, and wait
about half an hour for your eyes to adjust to the darkness. Many more stars appear
once your eyes are dark-adapted. Never go to a dark open place at night without an
adult.

In-text Questions — Page 236

Page 7 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

12.2 Night Sky Watching — planning an observation

Q1 Can we try to find any constellation or star of our choice on any night from our
location?

No — not any star on any night from any place. Three things decide whether you can see a
particular star or constellation.

WHAT EFFECT EXAMPLE FROM THE CHAPTER
DECIDES IT

Where you are Part of the sky is always hidden below The Pole Star is not visible from the southern
on Earth your horizon hemisphere

Which night of As Earth revolves round the Sun, different Orion is best seen in India from December to
the year constellations come into the night sky April, the Big Dipper in summer evenings

Local Clouds, moonlight, light pollution, smoke, In a big city only a few stars are seen; in
conditions dust, tall buildings and trees all hide stars Nubra, with almost no light pollution,
thousands are seen

So what should you do? Use a sky-mapping app or an online resource to find out when and in
which part of the sky your chosen object will be visible from your own town, and then pick a clear,
moonless night.

Why the Pole Star is invisible from the south: it sits above the Earth's North Pole.
For someone standing in the southern hemisphere, the bulge of the Earth itself
blocks that direction, so the star never rises above the horizon.

Activity 12.2: Let us try to locate — Page 238

Page 8 of 42

as e
Class 6 Science Chapter 12 Beyond Earth
a g l AglaSem · NCERT Solutions

12.2 Night Sky Watching — the Big Dipper and the Pole Star
co m
e m.
m as
ACTIVITY

.co a g l
a s emfor the Big Dipper during summer time in the early part of the night, say,
gl
Look
a
Q1
around 9 p.m. View the sky towards the northern part of the sky and identify the
Big Dipper.

com
m . ag
l a se
ag9 p.m. on a clear summer night, seven fairly bright stars
Observation: facing north at about
stand out high in the sky in the shape of a ladle (karchhi) — four stars making the cup and

co m
m.
three making a slightly curved handle.

o m l a se
c the constellation Ursa Major. g
This is the Big Dipper, known in India as Saptaṛiṣhi (the seven sages).
It lies .inside a
m
se middle star of the handle has a faint companion right next to it — if you can split the pair
aThe
agl with the naked eye, your eyesight and your sky are both good.
m a s
m.co
Tip: pick a night when the Moon is not in the sky. Moonlight washes out the fainter agl
l a se
g
stars, and you will need faint stars for the next step.
a

c o m
.
m at the two stars
s e
Once you identify the Big Dipper, try to locate the Pole Star. Look
a
om at the end of the Big Dipper's cup and imagineaaglstraight
Q2

. cpresent line passing

s e m through these towards the north. At about five times the distance between these
ag la two stars, the imaginary line will lead to another star which is not very bright. This

m
star is the Pole Star.

a se
. com a g l
sem

a
Method — the "pointer star" ltrick:
ag
1. Find the two stars at the outer end of the cup of the Big Dipper (the edge away from the

c o m
.
handle). These are the pointer stars.

s e m straight line through
2. Measure the gap between them with your eye. Now draw an imaginary

. om running away from the cup, towards the north. agla
cthem,
a sem3. Travel along that line for about five times that gap.
agl 4. You arrive at a lone, not very bright star with hardly any stars near it. That is the Pole Star
c
m .
e
(Polaris, Hindi Dhruva tārā).

m a s
co agl
5. Confirm it: the Pole Star is the last star of the handle of the Little Dipper (constellation Ursa

m .
e
Minor).

g l as
a

com
m .
m ase
.co


a g l Page 9 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Pole Star (Dhruva tārā)
the two pointer stars about 5 × this gap — always in the NORTH

Little Dipper

Saptaṛiṣhi (Big Dipper)

Star-hopping from the Saptaṛiṣhi to the Pole Star. The two stars at the open end of the cup point the
way; go about five times their separation. The lines are imaginary and are not seen in the sky.

Why the Pole Star does not move: the Earth spins about an axis, and the Pole Star
lies almost exactly along that axis, above the North Pole. A point on the axis does not
swing around as the Earth turns, so this one star stays put while all the others
appear to circle around it.

Check it yourself: take a magnetic compass with you. Once you have found the Pole
Star, check the compass — the star and the compass needle should both point
north.

Activity 12.3: Let us try to identify — Page 238

Page 10 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

12.2 Night Sky Watching — Orion and Sirius

ACTIVITY

Q1 In India, Orion is best viewed during the months of December to April after sunset.
So, look for it during that period. Three bright stars in a short straight line are
located around the middle of Orion (imagined to be the belt of a hunter). Identify
these three stars first, as this is the easiest way to find Orion.

Observation: between December and April, an hour or two after sunset, look towards the
eastern and then the southern sky. You will see three bright stars in a short, straight, almost
evenly spaced row — nothing else in the sky looks like this. That row is Orion's belt.
Once you have the belt, the rest of the hunter falls into place around it:

Two bright stars above the belt are the hunter's shoulders. The reddish one is Betelgeuse,
called Ārdrā in Indian astronomy.
Two bright stars below the belt are his feet. The brilliant blue-white one is Rigel.
Orion is often shown battling a bull (Taurus), with his dog (Canis Major) following behind.

Betelgeuse (Ārdrā)

Bellatrix

Orion

belt — 3 stars

extend the belt line eastwards
Sirius
brightest star in the night sky Rigel
Saiph

Orion the hunter: two shoulders, three belt stars in a row, two feet. Extending the belt line leads to
Sirius. The lines are imaginary.

Page 11 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Did you know? The belt stars are so evenly spaced and so nearly in a straight line
that many Indian villages call them teen tara or the three sisters. They are the easiest
starting point in the whole winter sky.

Q2 Once you identify Orion, it is easy to locate the very bright star Sirius which is
located close to Orion. Imagine a straight line passing through the three middle
stars of Orion and look along this line towards the east. This will lead to Sirius.

Method: stretch the line of the three belt stars out beyond the belt, towards the east, and
follow it. It runs straight into a fiercely bright, slightly bluish star that clearly outshines
everything else around it. That is Sirius.

Sirius is the brightest star in the whole night sky.

It belongs to the constellation Canis Major — the hunter's dog.

Its Indian name is Lubdhak.

Why it is so bright: two reasons together. Sirius is a genuinely hot, bright star, and it
is one of the nearest stars to us. Brightness in the sky always depends on both how
much light a star gives out and how far away it is.

Check it yourself: Sirius twinkles very strongly, often flashing red, white and blue
when it is low in the sky. This is because it is a point of light and our atmosphere
keeps bending its rays. A planet at the same height hardly twinkles — that is a quick
way to tell a star from a planet.

In-text Questions — Pages 238, 239 & 240
12.3 Our Solar System — the Sun, and what else is out there

Q1 Which star is closest to us?

The Sun. The Sun is a star — the star nearest to the Earth.

Page 12 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Distance of the Sun from the Earth ≈ 150 million km = 1 astronomical unit (au)

Next nearest star: Proxima Centauri, about 269000 au away

That is about 269000 times farther than the Sun.

Why this matters: because it is so close, the Sun looks like a huge disc and floods
the Earth with heat and light. Proxima Centauri is the same kind of object, but at
269000 times the distance it is not even visible to the naked eye.

Did you know? The astronomical unit (au) was invented precisely because
kilometres are clumsy for space. Saying "Jupiter is about 5 au from the Sun" is much
easier than writing 778 million km.

Q2 Our Sun is also a star. So how is it that the Sun appears big and lights up the sky
while the other stars look like bright dots in the night sky and are not even visible
during the day time?

The difference is distance, not size.

The Sun is very much closer to us than any other star, so it appears as a large, blazing disc.
It is about 100 times bigger than the Earth in diameter, and even so it looks small
compared with how big it really is, because it is 150 million km away.
All other stars are enormously farther — the nearest is 269000 times as far. At that distance
even a giant star shrinks to a point of light. Many of those points are actually bigger than
our Sun.
During the daytime the Sun's light is so overwhelmingly bright — and the air scatters it all
over the sky — that the feeble light of the other stars is completely drowned out. The stars
have not gone anywhere; we simply cannot pick them out against a bright sky.

An everyday parallel: a candle flame is easily seen in a dark room, but hold the
same candle next to a stadium floodlight and it disappears. The candle is still
burning — it is just outshone. The stars are the candles and the daytime sky is the
floodlight.

Page 13 of 42

as e
Class 6 Science Chapter 12 Beyond Earth
a g l AglaSem · NCERT Solutions

co m
m.
Did you know? An astronaut standing on the Moon, which has almost no

as e
com l
atmosphere to scatter sunlight, can see the stars even while the Sun is up. It is our
. a g
m
air, lit by the Sun, that hides them from us.

l a se
ag

co m
ag
Are stars the only objects in the sky? Or, are there more objects which we may not
.
Q3

em
as
have noticed?

a g l

There are many more objects. Stars are only the most obvious ones. Our Earth, along with
co m
several other kinds of object and the Sun, together form our Solar System.
e m.
c o m g l as
. a
a s em
OBJECT WHAT IT IS EXAMPLE

aglThe Sun A star — the largest and heaviest object of the Solar Source of almost all the energy in the

s
System Solar System

com a
Large, nearly spherical bodies.that
e m agl
as
Planets revolve around the Mercury … Neptune (eight in all)
Sun
a g l
Satellites Bodies that move around planets Earth's Moon; Mars has two moons
(moons)
co m
m .
m as e
.co l
Asteroids
g
Small, rocky, irregular bodies, mostly between Mars The asteroid belt

em
and Jupiter
a
a s
agl Comets Dust, gas, rock and ice; grow a long tail near the Sun Halley's Comet (Dhūmaketu)

se m
com l a
Dwarf planets Bodies that revolve round the Sun but do not meet the Pluto

. a g
m
full definition of a planet

gl ase
a
The movement of an object around the Sun is called revolution.

co m
.
The spinning of a body about its own axis is called rotation.
e m
m l as
.co
Earth: one revolution ≈ 1 year | one rotation ≈ 24 hours = one day
a g
se m
g l a
a c
.
Tip: do not mix the two words. Revolution = going round something else (Earth round
the Sun). Rotation = spinning on the spot (Earth on its own axis). A merry-go-round
s e m
m a
rotates; you revolve around its centre.
e m . co agl
g l as
a

co m
m .
m as e
.co


a g l Page 14 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

In-text Questions — Pages 242 & 243
12.3 Our Solar System — spotting planets, telescopes, satellites

Q1 Can we identify a planet also the way we identified the constellations?

Yes, planets can be found in the sky — but not by their pattern. Planets keep moving among
the stars, so they are never part of a fixed shape. You identify them by brightness, position and
behaviour instead.

Venus is the easiest. After the Sun and the Moon it is the brightest object in the sky, seen
low in the east before sunrise or low in the west after sunset — hence Morning Star or
Evening Star, although it is not a star at all.
Mercury, Mars, Jupiter and Saturn can also be seen with the naked eye. Mars looks
distinctly reddish.
The give-away test: stars twinkle a lot; planets do not. A steady, non-twinkling bright "star"
is almost certainly a planet.
A sky-map app will confirm which planet you are looking at on a given night.

Why planets hardly twinkle: a star is so far away that it is a mere point of light, and
the moving air bends that single thin beam this way and that — so it flickers. A
planet is close enough to be a tiny disc — many points of light side by side — and
their flickers average out, so the light looks steady.

Q2 How can we see the planets which are not visible to the naked eye?

Use a pair of binoculars or a telescope. Uranus and Neptune are far too faint for the naked
eye, and even the bright planets show no detail without help.

A telescope collects far more light than the small pupil of your eye, so it makes objects look
brighter, and it also makes them look larger. It therefore shows many dim objects that we
cannot see directly.
Binoculars are cheaper, easy to hold and already enough to show Jupiter's four big moons
as tiny dots in a line.
You do not need to own one. Watch out for a night sky watching event in your region —
many Higher Education Institutions, Amateur Astronomy Clubs, museums and planetariums
organise them for school students.

Page 15 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Did you know? Through even a small telescope you can see the rings of Saturn, the
craters on the Moon and the phases of Venus — all three were first seen through a
telescope only about four hundred years ago.

Q3 We know that planets move around the Sun. Are there any objects that move
around planets?

Yes — they are called satellites. Objects that move around planets are commonly called
satellites, and they are smaller than the planets they go around. The natural satellites of
planets are called moons.

PLANET NUMBER OF MOONS

Earth 1 — the Moon

Mars 2

Jupiter, Saturn, Uranus, Neptune A large number each

Our Moon at a glance:

Takes about 27 days to complete one revolution around the Earth.
About 3,84,000 km away — our nearest neighbour in space.
About a quarter of the Earth's diameter.
Has hardly any atmosphere, no water and no life.
Its surface is dotted with circular, bowl-like craters, formed mostly by asteroids and rocks
from space crashing into it. With no air, water or life to wear them away, the craters survive
for an extremely long time.

Page 16 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

India and the Moon (from the chapter, page 245). India has launched three
Chandrayaan missions: Chandrayaan-1 in 2008, Chandrayaan-2 in 2019 and
Chandrayaan-3 in July 2023. Chandrayaan-3's Vikram lander, carrying the Pragyan
rover, soft-landed on 23 August 2023, making India the first country in the world
to land near the little-explored south pole of the Moon. To mark it, the
Government of India declared 23 August as National Space Day. A fourth mission,
Chandrayaan-4, is being planned, which aims to bring back soil and rock samples
from the Moon.
Not in this chapter: ISRO's other well-known missions — Mangalyaan (the Mars
Orbiter Mission, launched 2013) and Aditya-L1 (India's first solar observatory,
launched September 2023) — are not mentioned in this chapter, so do not write
them in an answer unless a question asks about ISRO in general.

Why "satellite" is a wider word than "moon": in general, any object that moves
around a much larger object can be called its satellite. In that sense the Earth can be
called a satellite of the Sun. A moon is specifically a natural satellite of a planet — as
opposed to the artificial satellites we launch.

Page 17 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Beyond this chapter — why the Moon changes shape. The chapter does not
discuss the Moon's phases, but you will surely have noticed them. Half of the Moon
is always lit by the Sun. As the Moon revolves around the Earth, we see that lit half
from different angles, so a different amount of it faces us each night. The full cycle
takes about 29½ days. The phases are not caused by the Earth's shadow — the
Earth's shadow falls on the Moon only rarely, and that is a lunar eclipse, a completely
different event.

New Moon Waxing Crescent First Quarter Waxing Gibbous
(Amāvasyā) (bāl chandra) (half Moon)

Full Moon Waning Gibbous Last Quarter Waning Crescent
(Pūrṇimā) (half Moon)

The eight phases of the Moon, in order. The orange part is the sunlit half that we can see from
the Earth. In India the waxing half of the month is the Śhukla pakṣha and the waning half the
Kṛiṣhṇa pakṣha.

Activity 12.4: Let us try to identify — Page 243
12.3 Our Solar System — locating Venus

ACTIVITY

Q1 With the help of an app, Venus can be located either at dawn or at dusk. When you
are viewing at dawn, look for it near the Eastern direction before sunrise. When you
are viewing at dusk, look for it near the Western direction after sunset.

Observation: Venus appears as a single, extremely bright, steady white "star" quite low in the
sky, close to where the Sun is about to rise or has just set.

Page 18 of 42

as e
Class 6 Science Chapter 12 Beyond Earth
a g l AglaSem · NCERT Solutions

co m
m.
WHEN YOU OBSERVE WHERE TO LOOK WHAT VENUS IS CALLED

m as e
.co
At dawn, just before sunrise Low in the East
a
Morning Star
g l
se m
g l a
At dusk, just after sunset
a
Low in the West Evening Star

How to be sure it is Venus and not a star:

co m
e m .
It is far brighter than any star — after the Sun and the Moon it is the brightest object in ag
the sky.
g l as
a
It shines with a steady light and does not twinkle much.

m
The sky around it is still twilight-bright, and no star can be seen there yet.
co
m.
Check the app: it will name the object for you.

o m l a se
.c is only seen near sunrise or sunset: Venus travelsa g round the Sun inside
m
se orbit, so from the Earth it never appears far away from the Sun in the sky. It
Why Venus

g l a
Earth's
a is either a little ahead of the Sun (evening) or a little behind it (morning), and never
overhead at midnight.
m a s
em
.co agl
a s
a gl Śhukra in India. Even though it is farther from the
Did you know? Venus is called
Sun than Mercury, Venus is hotter than Mercury — its thick atmosphere traps the
heat and does not let it escape.
co m
m .
m as e
.co a g l
e m
las Questions — Pages 246 & 247
ag12.4 The Milky Way Galaxy and 12.5 The Universe
In-text

se m
com g l a
m . a
ase
Q1 What is beyond the Solar System?

agl

co m
.
Beyond the Solar System lie other stars — and our whole Solar System is only a tiny part of
a galaxy.
se m
o m l a
.cOn a moonless night, from a really dark place, you can seeaga faint band of light stretching
m across the sky roughly from north to south. That band is the Milky Way Galaxy, called
l a se
ag
.c
Ākāśha Gangā in India.
A galaxy is a huge system containing millions to billions of stars.
s e m
m a
. co
Our Solar System is part of the Milky Way Galaxy, and the Sun is just one of its enormous
m agl
number of stars.
l a se
ag the Sun, Proxima Centauri, is about 269000 au away — and it too
The nearest star beyond
belongs to the Milky Way.

co m
m .
m ase
.co


a g l Page 19 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Why the Milky Way looks like a band and not a blob: our galaxy is shaped rather
like a flat disc, and we sit inside that disc. Looking along the plane of the disc we see
huge numbers of distant stars piled up behind one another, and their combined
glow makes a milky band. Looking out of the disc we see far fewer stars.

Q2 What is beyond the Milky Way Galaxy?

Many, many more galaxies. Beyond the Milky Way, in outer space, there are countless other
galaxies, each with its own millions to billions of stars.

Planets → revolve around a star

Stars, in millions to billions → make a galaxy

Countless galaxies together → make the Universe

Scientists study these distant galaxies to understand how stars are born, how galaxies form and
how the Universe itself works.

Did you know? The Indian Astronomical Observatory at Hanle, Ladakh, sitting
on Mount Saraswati at one of the highest observatory sites in the world, is one of
the places from which Indian scientists study such distant objects.

Q3 Is there life anywhere else in the Universe?

We do not know yet — and that is the honest scientific answer. So far, scientists have found
no evidence of life anywhere except on the Earth, but the search is very much alive and
continuing.

The search is directed mostly at exoplanets — planets discovered revolving around other
stars in our galaxy.
Scientists look for planets at the right distance from their star, where water could stay liquid,
and then examine the light coming from them for signs of gases that living things might
produce.
Within our own Solar System, Mars and some icy moons of Jupiter and Saturn are also being
searched.

Page 20 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Why "we do not know" is a good answer: in science, saying that the evidence is
not yet in is far better than guessing. A scientist keeps the question open, keeps
testing, and changes the answer only when observation demands it. That is exactly
the spirit of enquiry this book began with in Chapter 1.

Let us enhance our learning — Pages 249 – 251
Chapter exercise

Q1 Match the column: Column I — (i) Satellite of Earth, (ii) Red planet, (iii)
Constellation, (iv) Planet which is commonly called an evening star. Column II — (a)
Orion, (b) Venus, (c) Mars, (d) Moon.

COLUMN I MATCH COLUMN WHY
II

(i) Satellite of Earth (d) Moon The Moon is the Earth's only natural satellite;
it revolves around the Earth in about 27 days.

(ii) Red planet (c) Mars Mars looks red because the soil on its surface
is reddish in colour.

(iii) Constellation (a) Orion Orion is a constellation, imagined as a hunter
with a three-star belt.

(iv) Planet commonly (b) Venus Venus shines brightly in the west after sunset
called an evening star — but it is a planet, not a star.

(i) → (d) (ii) → (c) (iii) → (a) (iv) → (b)

Tip: Venus is also called the Morning Star when it is seen in the east before sunrise.
Same planet, different time of day.

Page 21 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Q2 (i) Solve the following riddle. My first alphabet is in MAN but not in CAN / My second
alphabet is in ACE and also in FAN / My third alphabet is in RAT and not in CAT / My
fourth alphabet is in SUN but not in FUN / I am a planet that moves around the Sun.
(ii) Make two similar riddles by yourself.

(i) Solving the riddle, letter by letter:

CLUE WORKING LETTER

In MAN but not in CAN MAN = M, A, N · CAN = C, A, N → the odd one out is M M

In ACE and also in FAN ACE = A, C, E · FAN = F, A, N → common letter is A A

In RAT but not in CAT RAT = R, A, T · CAT = C, A, T → the odd one out is R R

In SUN but not in FUN SUN = S, U, N · FUN = F, U, N → the odd one out is S S

M + A + R + S = MARS

Answer: Mars, the Red Planet — the fourth planet from the Sun.

(ii) Two riddles of my own. Solve them the same way.

Riddle 1
My first letter is in VAN but not in CAN
My second letter is in NET and also in ELM
My third letter is in NUT but not in CUT
My fourth letter is in USE but not in SEA
My fifth letter is in SUN but not in RUN
After the Sun and the Moon, I am the brightest object in the sky.
Answer: VENUS

Riddle 2
My first letter is in MAT but not in CAT
My second letter is in COT but not in CAT
My third letter is in TOP and also in DOG
My fourth letter is in NET and also in SUN
I am the Earth's natural satellite.
Answer: MOON

Page 22 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

How to build your own: write the answer first, then for every letter find two short
words — one that contains the letter and one that does not, but which are otherwise
as similar as possible (RAT / CAT). For a letter you want to keep, use two words that
share only that letter (ACE / FAN).

Q3 Which of the following is not a member of our Solar System? (i) Sirius (ii) Comets (iii)
Asteroids (iv) Pluto

Answer: (i) Sirius

Why: Sirius is a star — the brightest star in the night sky — belonging to the constellation Canis
Major. It lies far outside the Solar System and does not revolve around the Sun.

(ii) Comets — members. They are icy-rocky bodies; many revolve around the Sun and return
periodically.
(iii) Asteroids — members. Small rocky bodies, most of them in the asteroid belt between
Mars and Jupiter.
(iv) Pluto — a member. It revolves around the Sun beyond Neptune; since 2006 it is classified
as a dwarf planet, but it is still part of the Solar System.

Tip: the test for membership of the Solar System is simple — does it go round our
Sun? Sirius does not; it is a sun of its own.

Q4 Which of the following is not a planet of the Sun? (i) Jupiter (ii) Pluto (iii) Neptune
(iv) Saturn

Answer: (ii) Pluto

Why: Pluto revolves around the Sun and lies farther out than Neptune, but it is not counted as
a planet. It is smaller than the Earth's Moon. When many more small bodies like it were
discovered, the International Astronomical Union (IAU) in 2006 redefined what an object
must be in order to be called a planet. Under that definition Pluto and similar small bodies are
now called dwarf planets.

Page 23 of 42

as e
Class 6 Science Chapter 12 Beyond Earth
a g l AglaSem · NCERT Solutions

Jupiter, Neptune and Saturn are three of the eight planets of the Sun.
co m
e m.
m l as
.co a g
Did you know? Pluto was discovered in 1930 and was called the ninth planet for 76

s em
years. Science changed its mind when new evidence arrived — which is exactly how
a
gl is supposed to work.
ascience

co m
em . ag
Q5
l as
Which is the brighter star, the Pole Star or Sirius?
g
a
m

co
em.
m l as
.co a g
Sirius is the brighter star.

a s em
a gl Sirius, in the constellation Canis Major, is the brightest star in the whole night sky. It is
impossible to miss once you follow the line of Orion's belt to the east.
m a s
. c o agl
The Pole Star (Polaris, Dhruva tārā) is not very bright. The chapter itself warns you to
choose a night with no Moon and nom
a s e clouds precisely because the Pole Star is faint.

agl
Why the Pole Star is still the more useful of the two: importance in the sky has
nothing to do with brightness. The Pole Star matters because it is the one star that
co m
m .
e
stays almost fixed in the north all night and all year, so it can be used to find
m l as
.co g
direction. Sirius, for all its brilliance, moves across the sky like every other star.
m a
l a se
ag
se m
com g l a
m . a
ase
agl

co m
m .
m as e
.co a g l
se m
g l a
a c
m .
m a s e
e m . co agl
g l as
a

co m
m .
m ase
.co


a g l Page 24 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Q6 An artist's representation of the Solar System is given in Fig. 12.12. Is the order of
the planets correct? If not, write the correct order in the boxes in the figure.

Fig. 12.12, page 250 — an artist’s representation of the Solar System, with an empty box
below each planet. Redrawn.

No, the order in Fig. 12.12 is not correct. Two pairs of planets have been swapped.
Reading the figure outward from the Sun, the artist has drawn: Mercury, Earth, Venus, Mars,
Jupiter, Uranus, Saturn, Neptune. Compare that with the true order:

BOX PLANET DRAWN IN FIG. 12.12 CORRECT PLANET

1 Mercury Mercury correct

2 Earth (blue, with clouds) Venus swapped

3 Venus (orange-brown) Earth swapped

4 Mars Mars correct

5 Jupiter Jupiter correct

6 Uranus (pale blue, thin upright ring) Saturn swapped

7 Saturn (yellow, broad rings) Uranus swapped

8 Neptune Neptune correct

So the boxes should be filled, from the Sun outwards, as:

Page 25 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Mercury → Venus → Earth → Mars → Jupiter → Saturn → Uranus → Neptune

increasing distance from the Sun

5 6 7 8
1 2 3 4

Mercury Earth Uranus
Jupiter
Venus Mars Neptune
Sun Saturn
asteroid belt

The correct order of the eight planets outward from the Sun. Sizes and distances are not to scale.

Tip — a sentence to remember the order: My Very Educated Mother Just Served
Us Noodles → Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

How to spot the mistake yourself in a picture: Earth is the blue-and-white one
(water and clouds); Venus is plain yellowish-brown; Saturn has broad, obvious rings
lying flat; Uranus is a small pale blue-green ball with a thin ring standing almost
upright. In Fig. 12.12 the blue-and-white ball sits at position 2 and the ringed yellow
giant at position 7 — both are one place out of turn.

Page 26 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Q7 A portion of night sky with stars is shown in Fig. 12.13. Look carefully and identify
the groups of stars that form the patterns—the Big Dipper and the Little Dipper.
Draw lines to connect the stars for these patterns and label them. Also, identify and
label the Pole Star. You may refer to Fig. 12.4 for help.

Fig. 12.13, page 250 — a portion of the night sky with stars.

Page 27 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Big Dipper

Little Dipper

Pole star

Fig. 12.4, page 235 — the Big Dipper, the Little Dipper and the Pole Star, given in the
chapter as help for this question. The lines are not in the sky; they are drawn only for
easy identification.

How to work on the figure in your book:

1. Find the seven brightest dots in the upper-left part of Fig. 12.13. Four of them form a
slightly slanted rectangle (the cup) and three trail away from one corner in a gentle curve
(the handle). Join them — that is the Big Dipper (Saptaṛiṣhi).
2. Take the two stars at the outer edge of the cup, the edge away from the handle. Draw a
light straight line through them, continuing away from the cup.

Page 28 of 42

as e
Class 6 Science Chapter 12 Beyond Earth
a g l AglaSem · NCERT Solutions

3. Measure the gap between those two stars and travel about five times that gap along the
co m
line. You reach a lone, fainter star — mark it Pole Star.
se m.
o m l a
.c That smaller ladle is the Little Dipper. Note that the PoleagStar is at the end of its
4. Starting from that star, join a short curved handle of three stars and then four stars forming
a smallm
se
cup.
l a
ag
handle.

Your finished figure should look like this:

co m
e m . ag
g l as
pointer stars
a about 5 × this gap
Pole Star

co m
em.
m l as
m .co a g
l a se
a g
m a s
.co agl
Little Dipper

se m
g l a
a

co m
m .
m ase
.co a g l
se m
g l a Big Dipper (Saptaṛiṣhi)
a
se m
com a
The completed answer for Fig. 12.13 — Big Dipper, Little Dipper and the Pole Star at the end of the

.
Little Dipper's handle.
a g l
m
ase
agl
Tip: use a pencil and a ruler and press lightly, so you can rub out and try again. Only
the bright dots belong to the patterns; ignore the faint ones scattered in between.
co m
m .
m as e
.co a g l
se m
g l a
a c
m .
m a s e
e m . co agl
g l as
a

co m
m .
m as e
.co


a g l Page 29 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Q8 A portion of the night sky is shown in Fig. 12.14. Draw lines to connect the stars for
Orion and label the star Sirius. You may refer to Fig. 12.3.

Fig. 12.14, page 251 — a portion of the night sky.

Sirius

Orion Taurus
Canis
Major

Fig. 12.3, page 234 — some constellations and stars, given in the chapter as help for this
question. The red lines are not in the sky; they are drawn only for easy identification.

How to work on the figure in your book:

1. Look near the middle of Fig. 12.14 for three fairly bright dots very close together in a
short, straight, evenly spaced row. That is Orion's belt — always find it first.

Page 30 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

2. Above the belt, mark the two bright stars that form the hunter's shoulders (one of them,
Betelgeuse, is the brighter, redder one).
3. Below the belt, mark the two bright stars that form the feet (the brilliant one is Rigel).
4. Join shoulder → belt end → foot on each side, and join the two shoulders across the top. You
now have the tall hourglass shape of Orion.
5. Now extend the line of the three belt stars towards the east (in the figure, away from the
belt on the lower side). The first really brilliant star you meet along that line is Sirius. Label it.

Your finished figure should look like this:

Betelgeuse

Orion

belt — 3 stars

extend the belt line
Sirius
Rigel

The completed answer for Fig. 12.14 — Orion joined up, and Sirius found by extending the line of the
belt.

Why the belt is the key: three stars of almost equal brightness, almost equally
spaced, in an almost perfect straight line, occur nowhere else in the sky. Once you
have the belt, every other star of Orion is fixed relative to it — and so is Sirius.

Q9 From Earth, you can see stars fading away at dawn and appearing at dusk. During
the day we do not see the stars. Explain why.

The stars are shining all day long. They are simply drowned out by sunlight.

Page 31 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Once the Sun rises, its light falls on the air above us and is scattered in every direction by
the gases and dust in the atmosphere. This scattered light is what makes the whole daytime
sky glow bright and blue.
The light reaching us from any other star is extremely feeble, because every one of them is
enormously far away.
A faint light cannot be picked out against a very bright background. So against the glowing
daytime sky, the stars become invisible — not absent.
At dusk the Sun goes below the horizon, the scattered light dies away, the sky background
darkens, and one by one the brightest stars begin to show. At dawn the reverse happens
and they fade out.

An everyday parallel: switch on the torch of your mobile phone in a dark room and
it looks dazzling. Take it out into bright noon sunlight and you can barely tell it is on.
The torch has not changed — the background has.

Did you know? On the Moon there is almost no atmosphere, so there is nothing to
scatter sunlight into a bright sky. The lunar sky stays black, and an astronaut can see
the stars even while standing in full sunlight. That proves it is our air, not the Sun
itself, that hides the stars from us.

Q10 During a clear night, try to observe the Big Dipper 3–4 times at an interval of 2 to 3
hours. Also try to locate the Pole Star each time. Does the Big Dipper appear to
move? Draw a rough sketch to illustrate this, mentioning the time in each case.

Observation: yes, the Big Dipper appears to move — but the Pole Star does not.

Over the night the whole Big Dipper appears to swing around the Pole Star in a circle,
moving anticlockwise as you face north.
The shape of the pattern never changes; only its tilt changes. It may stand upright at one
hour and lie almost on its side a few hours later.
The distance of each star from the Pole Star also stays the same — the whole pattern simply
rotates about that one point.
The Pole Star stays in the same place, in the north, at the same height above the horizon,
all night long.

Page 32 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

The sky turns through 360° in about 24 hours

→ about 15° in one hour

→ about 30° to 45° in an interval of 2 to 3 hours

Rough sketch (three observations, 3 hours apart):

Pole Star — does not move

9 p.m.

12 midnight
3 a.m.

the whole pattern swings anticlockwise around the Pole Star

The same Saptaṛiṣhi seen at 9 p.m., midnight and 3 a.m. The shape is unchanged; only its position
around the fixed Pole Star has turned, by about 45° every three hours.

Why it happens: the stars are not really moving across our sky — the Earth is
rotating on its axis, once in about 24 hours. Standing on a spinning Earth, we see
the whole sky appear to turn the opposite way. The Pole Star lies almost exactly on
the line of the Earth's axis, so it is the one point that does not swing round, and
every other star seems to circle about it.

Check it yourself: at each observation, hold your notebook the same way up and
sketch the dipper together with the horizon and the Pole Star. Write the time beside
each sketch. After three sketches the turning is unmistakable.

Page 33 of 42

as e
Class 6 Science Chapter 12 Beyond Earth
a g l AglaSem · NCERT Solutions

co m
m.
Think about the night sky and write a poem or a story on it.
e
Q11

m l as
.co a g
a s em
a glis your own creative work, so there is no single right answer. A good piece should use
This
things you have actually learnt in this chapter — the Saptaṛiṣhi, the Pole Star, Orion's belt,

co m
ag
Sirius, the Milky Way, a comet, the craters of the Moon — rather than vague words like

m .
e
"twinkling diamonds".

g l as
a
What a good answer must contain:

One or two real objects of the night sky, named correctly.

co m
m.
Something true about them (the Pole Star stays in the north; Sirius is the brightest star; a
comet grows a tail near the Sun).
m as e
.co
A feeling — wonder, curiosity, a question you would like answered.
a g l
a s em
agl Sample answer — a poem
The Lamp That Never Moves
m a s
em
.co agl
s
Seven sages carry a ladle of light,
a
l night.
slowly they circle the roof ofgthe
a
They swing and they lean, they turn and they go,
but one small lamp in the north hangs low.
co m
m .
m as e
.co
It is not the brightest, it is not the best,
a g l
s e m sailors have trusted it more than the rest.
yet

agla For Orion may march and Sirius may burn —
m
the Dhruva alone does not wander or turn.

a se
. com a g l
e m
And under that lamp, on a cold Ladakh night,

g l aswith light,
a
the Ākāśha Gangā spills over
a river of stars that no bucket can hold,
and I am a speck on a planet of gold.
co m
m .
m as e
.co a g l
se m
g l a
a c
m .
m a s e
e m . co agl
g l as
a

co m
m .
m ase
.co


a g l Page 34 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Sample answer — a story (in brief)
Yangdol could not sleep. She wrapped her goncha around her, climbed to the flat
roof and lay down on the cold stone. Dorjay came up too, carrying his grandfather's
old brass compass.
"Look," he said, "the ladle has moved." At nine o'clock the Saptaṛiṣhi had stood
upright over the ridge; now, past midnight, it lay tilted on its side.
"It has not moved," said Yangdol. "We have. The Earth turned under us." She traced
the two pointer stars with her finger, counted five gaps, and stopped at a faint,
lonely star. Dorjay opened the compass. The needle and the star agreed: north.
Far above them the Ākāśha Gangā stretched from one mountain to the other.
Somewhere in that band of light, Yangdol thought, is a star with a planet, and on
that planet perhaps someone is lying on a roof, looking back at us. She fell asleep
still wondering.

Tip for writing your own: begin with something you have really seen — the Moon
behind a neem tree, a shooting star, the sky above your terrace during a power cut.
A true observation always makes a better opening line than an invented one.

Learning further — Pages 251 & 252
Projects and further exploration

PROJECT WORK

Q1 Try to find out the names of planets in your local language. Also, find out the stories
associated with stars and constellations in your region. Present these stories in a
pictorial form.

How to do this project: ask your grandparents, a local priest, a farmer or a fisherman — they
usually know the old names and the stories better than any book. Note the name, the language
and the story in your notebook, then draw it.
Sample answer — names of the naked-eye planets (the textbook itself gives the Sanskrit-
derived set on page 241):

Page 35 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

ENGLISH SANSKRIT / HINDI TAMIL TELUGU MALAYALAM

Mercury Budha Puthan Budhudu Budhan

Venus Śhukra Velli Shukrudu Shukran

Earth Pṛithvī Bhoomi Bhoomi Bhoomi

Mars Mangala Sevvai Kujudu / Angarakudu Chovva

Jupiter Bṛihaspati / Guru Guru Guruvu Vyazham

Saturn Śhani Sani Shani Shani

Sample answer — stories from the chapter and around India:

Central India (tribal communities): the four stars of the Big Dipper that make a rough
rectangle are grandmother's cot, and the other three stars are three thieves stealing it
away.
Konkan coast (fishermen): the same four stars are a boat, and the last three stars are the
neck of the boat.
Across India: the seven stars are the Saptaṛiṣhi, the seven sages, and the Pole Star is
Dhruva, the boy whose steadfastness earned him a fixed place in the sky.
Comets are called Dhūmaketu in Sanskrit, Pucchya-Taro (star with a tail) and Zendya-Taro
(star like a flag) by different tribes of India.

How to present it pictorially: take a black chart paper. Stick small silver or white
star stickers in the correct pattern. Over them, draw the imagined shape in thin
white chalk or a gel pen — the cot, the boat, the sages. Write the story in two or
three lines below each panel. Give your poster a title and display it in class.

Q2 If there is a planetarium or a science museum nearby, then you can visit it,
especially if a night sky observation session is scheduled by them. You will get to
see the Moon, the planets and the stars through a telescope. If you visit the
planetarium during daytime, you can also see their models, pictures and sky shows.

How to plan the visit:

1. Look up the planetarium or science museum nearest to you and check its show timings and
whether it holds night sky observation sessions. Museums, planetariums, Higher
Education Institutions and Amateur Astronomy Clubs all organise them.
2. Go with your teacher, parents or an adult. Carry a notebook and pencil.

Page 36 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

3. Before you go, list three questions you want answered — for example, "How big is the
telescope?", "Which planet is visible tonight?", "Why is Saturn's ring flat?"

What you will actually see:

OBJECT WHAT A SMALL TELESCOPE SHOWS

Moon Craters, mountains and the sharp line between the lit and unlit halves

Jupiter A small striped disc with up to four tiny moons in a line beside it

Saturn The rings — the sight most visitors remember for life

Venus A brilliant crescent, like a miniature Moon

Star clusters Kṛittikā (Pleiades) resolves into dozens of separate blue stars

Tip: in a daytime visit do not skip the sky show under the dome. It can compress a
whole night's rotation into a few minutes, so you can actually watch the Saptaṛiṣhi
swing around the Pole Star — the very thing Question 10 asks you to observe over
several hours.

Q3 Find out if the increasing light pollution is causing problems for humans, wildlife
and the environment. Write an action that you would take at the personal level to
control light pollution.

Yes — light pollution causes real harm, and it is growing sharply all over the world. The
excessive artificial light we throw into the night sky affects three groups.

AFFECTED PROBLEM CAUSED

Humans Bright light at night disturbs sleep and the body's day–night rhythm; glare from badly aimed
lamps dazzles drivers; energy — and money — is wasted lighting up the sky instead of the
ground.

Wildlife Insects swarm around lamps all night and die, and fewer insects means less food for birds and
less pollination. Migrating birds get confused by lit-up buildings. Newly hatched sea turtles on
our coasts crawl towards bright hotel lights instead of the sea. Bats, owls and other night animals
lose their hunting grounds.

Environment The night sky is lost to most city children. Astronomers cannot study faint objects, which is why
and science dark sky reserves and parks — like the Hanle Dark Sky Reserve in Ladakh, notified in
December 2022 — are now being created and protected.

Page 37 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Sample answer — what I will do at my personal level:

Switch off the outdoor bulb of our house and the terrace light when nobody is using them,
and ask my family to do the same.
Ask my father to fit a simple shade or hood over our gate lamp so the light falls downwards
on the path and not sideways into the sky and the neighbour's window.
Use a lower-power, warm-coloured bulb outside instead of a glaring white one.
Draw the curtains at night so indoor light does not spill outside.
Make a poster for my school notice board — "Light the ground, not the sky" — and explain to
my class what light pollution costs us.

Why this small action matters: unlike most pollution, light pollution disappears the
instant the cause is removed. Switch a badly aimed lamp off and the sky above it is
clean again that same night. Very few environmental problems can be repaired that
quickly.

Q4 Find out the weather conditions due to which the Indian Institute of Astrophysics
(IIA) found Hanle, Ladakh a suitable place to set up an observatory.

The Indian Astronomical Observatory at Hanle stands on the highest peak of the Digpa-ratsa-Ri
range — now renamed Mount Saraswati — at a height of about 4,500 m. It is one of the
highest observatory sites in the world. IIA chose it because almost every condition an
astronomer needs comes together there.

CONDITION AT HANLE WHY IT HELPS A TELESCOPE

Very few clouds — a large number of More nights available for observation; a cloudy site wastes an
clear nights every year expensive telescope

Extremely dry, cold-desert air with very Water vapour absorbs infrared light; dry air lets much more of it
little water vapour reach the telescope

Very high altitude — much of the Less air to look through means sharper, steadier images
atmosphere is already below you

Calm, steady air with little turbulence Star images stay crisp instead of shimmering and blurring

Remote and thinly populated — almost Very faint objects can be recorded; this is why the area was declared
no light pollution the Hanle Dark Sky Reserve in December 2022

Very little dust and industrial haze Cleaner air scatters less light and keeps the sky background dark

Page 38 of 42

as e
Class 6 Science Chapter 12 Beyond Earth
a g l AglaSem · NCERT Solutions

co m
m.
Did you know? One of the telescopes at Hanle is the Himalayan Chandra

m
Telescope, named after the Nobel Prize winning scientist Subrahmanyan
o l a se
.c a g people have
m
Chandrasekhar. The reserve is open to the public all year, and local

l a segiven small telescopes and trained by IIA as Astronomy Ambassadors — a
g example of astro-tourism helping a whole region.
been
afine

co m
e m . ag
g l as
a

co m
em.
m l as
m .co a g
l a se
a g
m a s
m .co agl
l a se
a g

co m
m .
m as e
.co a g l
se m
g l a
a
se m
com g l a
m . a
ase
agl

co m
m .
m as e
.co a g l
se m
g l a
a c
m .
m a s e
e m . co agl
g l as
a

co m
m .
m ase
.co


a g l Page 39 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

Q5 If you enjoy doing embroidery, try to embroider on a dark coloured cloth the
constellations that you have seen (Fig. 12.15). Otherwise, you may use your
creativity and depict constellations in multiple other ways using various art and
craft ideas.

Fig. 12.15, page 252 — constellations embroidered on a dark cloth held in an embroidery
hoop. Redrawn sketch; see the textbook for the photograph.

How to make the embroidered star chart:

1. Take a piece of dark blue or black cloth and stretch it in an embroidery hoop.
2. Copy the constellation from Fig. 12.3 or Fig. 12.4 on to tracing paper. Mark each star with a
dot, making the dot bigger for a brighter star.
3. Transfer the dots to the cloth with a fine tailor's chalk.

Page 40 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

4. Work each star as a French knot or a small cluster of straight stitches in white, silver or pale
yellow thread. Use a bead or a sequin for the brightest star — Sirius, or Betelgeuse in red.
5. If you wish, join the stars with a very fine running stitch in grey thread to show the
imagined pattern, and embroider the name below in back stitch.

Other ways to depict a constellation — pick any one:

Pin-prick lantern: prick the star pattern into black chart paper with a needle, roll it into a
cylinder and stand a torch inside. The pattern appears on the ceiling of a dark room.
Thread-and-nail art: hammer small nails into a painted wooden board at the star positions
and stretch white thread between them.
Rangoli / clay diyas: lay out the Saptaṛiṣhi on the floor with white rangoli powder, or place
tiny diyas at the seven star positions on Diwali.
Bottle-cap mosaic or glow paint: glue silver bottle caps, or dab glow-in-the-dark paint, on a
black sheet.
Class night-sky mural: each student embroiders or paints one constellation on a square,
and all the squares are stitched together into a single sky quilt for the classroom wall.

Tip: keep the relative distances and the relative brightness of the stars roughly
correct. A star chart is useful only if someone can hold it up against the real sky and
recognise the pattern.

Chapter at a glance
Stars shine with their own light. Groups of stars that appear to make a pattern were
called constellations. Today a constellation means a defined region of the sky — the
International Astronomical Union has divided the whole sky into 88 such regions.
The Pole Star (Dhruva tārā, Polaris) appears nearly stationary in the north, so it fixes the
north direction in the Northern hemisphere. Find it from the two pointer stars at the end of
the Big Dipper (Saptaṛiṣhi) cup — about five times the gap between them.
The Sun is a star — the one nearest to us. It is about 100 times bigger than the Earth in
diameter and about 150 million km away (that distance is called 1 astronomical unit, au). It
is the main source of energy on Earth.
A planet is a large, nearly spherical object that revolves around the Sun. The eight planets
in order of increasing distance are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus,
Neptune. The inner four are small and rocky; the outer four are giant, made mostly of gas
and ice, and have rings. Pluto is now a dwarf planet (IAU, 2006).
Objects that move around planets are satellites. The Moon is Earth's natural satellite —
about a quarter of Earth's diameter, 3,84,000 km away, one revolution in about 27 days,
with craters and almost no atmosphere. India's Chandrayaan-3 soft-landed near the
Moon's south pole on 23 August 2023, now National Space Day.

Page 41 of 42

Class 6 Science Chapter 12 Beyond Earth AglaSem · NCERT Solutions

The Sun + eight planets + their moons + asteroids + comets form the Solar System,
which is a tiny part of the Milky Way Galaxy (Ākāśha Gangā). Beyond it lie countless other
galaxies — together, the Universe.

Quick revision

TERM WHAT IT MEANS EXAMPLE FROM THE CHAPTER PAGE

Star A huge, extremely hot ball of gases that The Sun, Sirius, Proxima Centauri 233,
shines with its own light 238

Constellation A defined region of the sky, usually Orion, Taurus, Canis Major, Ursa Major 233
containing a familiar pattern of stars

Pole Star / The star that appears nearly fixed in the Located at about 5× the gap between 235
Dhruva tārā north; part of the Little Dipper the two pointer stars

Saptaṛiṣhi / Big The seven-star pattern lying in the Seen as a grandmother's cot, or a boat, 235
Dipper constellation Ursa Major in Indian folk stories

Nakṣhatra Indian term for a star or a group of stars Ārdrā = Betelgeuse, Kṛittikā = Pleiades, 234
Rohiṇī = Aldebaran

Light pollution Excessive artificial light at night Only a few stars are seen from a big 236
city

Revolution The movement of one object around Earth around the Sun: about 1 year; 240,
another Moon around Earth: about 27 days 244

Rotation The spinning of a body about its own Earth takes about 24 hours for one 240
axis rotation — that is a day

Planet A large, nearly spherical object that Mercury, Venus, Earth, Mars, Jupiter, 240–
revolves around the Sun Saturn, Uranus, Neptune 241

Satellite An object that moves around a planet The Moon; Mars has two moons; 244
Jupiter has many

Asteroid A small, rocky, irregularly shaped The asteroid belt; sizes from 10 m to 245
object; most lie between Mars and about 500 km
Jupiter

Comet A body of dust, gas, rock and ice that Halley's Comet, seen every 76 years; 245–
grows a long tail near the Sun called Dhūmaketu 246

Page 42 of 42