Download 1 - Blinklearning

UNIT
Work in yo
oo
k
1
t eb
ur no
The Universe
and the Earth
The Universe
Track 1
The Universe
The universe is everything that exists. It is so enormous that
scientists cannot measure distances in kilometres; they have
to use light years. A light year is the time it takes for light to
travel in one year; 10 trillion kilometres! Nothing travels faster
than light. Light travels at 299 792 458 metres per second!
The universe contains celestial bodies. Celestial bodies
are nebulae, stars, galaxies, comets, asteroids, meteorites,
satellites, planets and dwarf planets.
Our Universe is amazing!
• N
ebulae are clouds made up of dust and different types
of gases that form stars. Stars are made inside a nebula.
• Stars are huge spheres of very hot, glowing gas. Stars
produce their own light and energy. The Sun is a star.
• Galaxies are groups of millions of stars and nebulae.
• Satellites are objects that move around larger objects.
The Moon is a satellite.
• Comets are big balls of ice, mud and rock; they look like
they have tails.
A visual representation
of a galaxy.
• Asteroids are large rocks travelling in space; they revolve
around stars and planets.
• Meteorites are asteroids that crash into planets or stars.
• P
lanets orbit stars; they can be made of rock or gas and
are large spherical bodies. The Earth is a planet. A planet
does not emit its own light, but reflects the Sun’s light.
• Dwarf planets are smaller than planets.
A comet is a big ball of ice,
mud and rock.
1 Are the sentences True or False? Correct the false ones in your notebook.
1 Planets orbit stars.
3 A planet is smaller than a dwarf planet.
5 A planet emits its own light.
4
2 The Earth is a star.
4 Planets are spherical in shape.
6 Comets have tails.
Unit
Planetary systems: Our Solar System
A planetary system is a group of planets in the same area that orbit a
star. The Earth belongs to the planetary system called the Solar System.
Our Solar System is made up of all the celestial bodies that orbit the
Sun. It is in the galaxy called the Milky Way.
The star that we call the Sun is at the centre of the Solar System. It is an
enormous ball of gas. More than 1 400 000 Earths could fit inside of the
Sun! All of the other celestial bodies orbit around the sun. They do not
orbit it in a perfect circle; they orbit it in an elliptical shape.
The Sun provides light and thermal energy. The Earth is at the perfect
distance from the Sun to allow us to have life on Earth. It takes 365 days
for the Earth to rotate around the Sun. Between the orbits of Mars and
Jupiter are a group of rocks, called the asteroid belt.
The Solar System
Position of the Solar System
in the Milky Way
The paths of th
e
planets are
called orbi
ts
Planets
Mercury
Venus
Earth
Mars
and are e
lliptical in
Dwarf planets
Satellites
The Moon (is a satellite
of the Earth)
Pluto, Ceres, Eris…
Jupiter
Saturn
Uranus
Neptune
Comets
Halley, Hale-Bopp…
Asteroids
The majority are between
Mars and Jupiter
shape
Mars
THE
SUN
The Moon
Uranus
Venus
Pluto
Neptune
Earth
Jupiter
Saturn
Halley
THE SOLAR SYSTEM
scopes
Mercury
e
Tel
Track 2
1
1 F ind and correct the five mistakes in the paragraph.
A group of planets that orbit a star is called a planetary circle. The Earth
is at the centre of the Solar System. All of the celestial bodies orbit
around it. The Sun gives us light and kinetic energy. It takes 366 days
for the Earth to rotate around the Sun. No other planets have moons.
2 Study
the picture of the Solar System and answer the questions.
1 What are the names of the planets in the Solar System?
2 Name a dwarf planet.
3 What is the name of the satellite that orbits the Earth?
5
Track 3
The Earth and its movements
The Earth rotates around an imaginary line or central axis as it orbits the
Sun. The axis of rotation is tilted with respect to the Sun around 23º.
If we draw an imaginary line through the Earth, the place where the
line meets the surface of the Earth in the north is called the North Pole
and in the south it is called the South Pole.
The imaginary line around the Earth’s surface that is an equal distance
to the poles is called the Equator. The Equator divides the Earth into
the Northern Hemisphere and the Southern Hemisphere.
Equinoxes and solstices
The equinoxes are the days that the Sun shines directly on top of the
Equator. On these days, there are twelve hours of light all over the
world. The summer solstice is the longest day of the year and the
winter solstice is the shortest. When the days of sunlight are increasing
in one hemisphere, they are decreasing in the other. At the Equator,
the Sun rises and sets faster than at any other point on Earth.
In these positions, the Sun
illuminates both poles and day
and night both last 12 hours.
20th / 21 st of March
Spring equinox
SPRING
THE
SUN
20th / 21 st of June
Summer solstice
in the Northern
Hemisphere
SUMMER
The Sun’s rays are perpendicular
to the Tropic of Cancer and in the
Arctic Circle it is always daytime.
The days are long and the nights
are very short (summer in the
Northern Hemisphere). In the
Southern Hemisphere, the days
are short and the nights are long
(winter has begun).
WINTER
22nd / 23rd of September
Autumn equinox
21 st / 22nd
of December
Winter solstice
in the Northern
Hemisphere
AUTUMN
The seasons in the Northern and Southern Hemispheres
are always opposites.
SEASON
BEGINS
20th / 21 st of March
20th / 21st of June
22nd / 23rd of September
21 st / 22nd of December
NORTHERN
HEMISPHERE
SOUTHERN
HEMISPHERE
Spring
Summer
Autumn
Winter
Autumn
Winter
Spring
Summer
The exact dates of the equinoxes and solstices change every year.
1 S tudy the picture and answer the questions.
6
mparative
Co
3 W
hat is it like in the Arctic Circle when summer begins
in the Northern Hemisphere. Why?
nd superla
es
2 When is it summer in the Southern Hemisphere?
sa
tiv
1 When is it spring in the Northern Hemisphere?
Unit
Track 4
1
The Earth’s systems
The Earth is divided into three layers: the atmosphere, the
hydrosphere and the geosphere.
ATMOSPHERE
BIOSPHERE
GEOSPHERE
HYDROSPHERE
• The atmosphere is the layer that contains the Earth’s air and
surrounds the planet. It is about 1 000 kilometres thick.
• The hydrosphere consists of all of the water on Earth in its three
states: liquid, solid and gas (vapour).
• The geosphere is the densest part of the Earth; it is mainly rock.
1 W
hich layer of the Earth…
1 … contains all of the water found in its three different states?
2 … surrounds the entire planet and contains air?
3 … is made up of mainly rocks?
The layers of the geosphere
Track 5
The Earth is made up of different layers.
The four main layers are:
Crust
Mantle
Outer
core
Inner
core
• the crust • the outer core
• the mantle • the inner core
2 Study the image of the geosphere. Where do human beings live?
3 Which layer of geosphere do you think is the hottest? Explain your
answer.
7
Track 6
Spaceships in orbit
The atmosphere
• The troposphere is the part of the atmosphere that
is closest to the Earth. It contains most of the air that
we breathe. The air moves up and down, creating
most of the weather on the Earth.
• T
he stratosphere is above the troposphere. The air
moves very quickly, parallel to the Earth. This is the
area where most aeroplanes fly because they use less
fuel here. The currents are called jet streams. The
stratosphere contains a substance called ozone which
protects us from the Sun’s harmful ultraviolet rays.
Thermosphere
The atmosphere is divided into different layers.
Aurora borealis
High energy
solar radiation
• T
he mesosphere is above the stratosphere. It is the
coldest area of the atmosphere. The temperature
can drop to -130 °C. It is here that meteorites that
come close to the Earth burn up, and we can see
them as shooting stars.
• T
he exosphere has a thin atmosphere where the
lightest gases are.
80 km
Cosmic rays
Mesosphere
• T
he thermosphere is above the mesosphere. Here
temperatures can reach 2 000 °C in the highest part
and can drop by 200 ºC at night.
Mesopause
Stratopause
Atmospheric phenomena
Meteorological
observation balloon
Stratosphere
• C
louds are formed by water vapour. Water on Earth
evaporates and rises because of the heat of the Sun.
These water droplets attach themselves to dust
particles in the air and join together to form clouds.
When the clouds become very heavy, the water droplets
fall as rain or snow depending on the temperature.
50 km
Ultraviolet
radiation
Ozone
layer
• Precipitation can fall from the clouds as snow, rain,
or hail.
• Storms happen when masses of hot and cold air
collide.
1 In which layer of the atmosphere do humans live?
8
Tropopause
12 km
Troposphere
• W
ind is produced when air becomes warmer and
rises, while other air currents cool and sink.
Temperature
–100 °C
0 °C
+100 °C
Unit
The Earth’s crust and continents
The Earth’s crust only occupies 1% of the Earth’s total volume, but it is
extremely important because humans can live on the crust. The crust is
made of many different sheets of rock, or tectonic plates, which float
on top of the Earth’s mantle.
The four main landforms on the Earth are mountain ranges, plains,
plateaus, and valleys.
The continents
• Africa
• America
• Antarctica
• Asia
• Europe
• Oceania
A R
C
T
I C
O
C
E
A
N
Greenland
R
O
C
G
K
O
at
M
re
Y
Pl
UN
s
Pyren
ees
ra
er e
Si dr
a
M
PS
AL
Ca
E
Plain
PE
Elbrus
5 642
rp
a
Mt thia
s. n
CAU
.
CA
SU
E S
6 960
Pa
m
pa
s
A
S
Arctic Circle
I
A
Mongolian
Plateau
S
H
LAS
AT T S .
M
GOBI
DESERT
IM
AL
S A H A R A
Deccan
Plateau
AFRICA
Centr al
S i ber i an
Pl ateau
Western
Siberian
Plain
PA C I F I C
OCEAN
A YA S
Tropic of Cancer
Everest 8 848
Ethiopian
Highlands
Puncak Jaya
INDIAN
5 030
Equator
OCEANIA
5 895
OCEAN
KALAHARI
DESERT
Australia
GREAT
VICTORIA
DESERT
Dividing
at ge
re an
G R
Brazilian
Plateau
D
Aconcagua
OC EAN
N
Kilimanjaro
PAC IFIC
5 000
A
n
pea
uro
t E
O
a
e
R
r
G
U
N
O C EA
A N
Peak
4 000
an
AMERICA
Lake
Elevation (m)
8 000
hi
ac
al .
ppMts
A
IC
NT
LA
AT
INS
River
ain
TA
World relief
SC
I
AV
IN .
D TS
N
A M
U R A L M TS
Track 7
1
Tropic of
Capricorn
3 000
2 000
1 000
500
A
N
T A
R
C
T
I
C
O
C
E
A
N
Antarctic Circle
200
0
-500
Ice shelf
A
N
T A
R
C T
I
C
A
0 1 000 2 000 3 000 4 000 5 000 km
1 L ook at the map and answer the questions.
1 Which area has the highest altitude?
2 Which areas are covered in ice?
3 How could we describe the land or relief
of Europe?
Sci-find
What happens when tectonic
plates collide? Find out!
9
The globe
Track 8
Globes and world maps
The Earth is a three-dimensional sphere;
however, a map is only two-dimensional.
Therefore, we can use three-dimensional
globes to show the Earth and its
components more accurately.
On both globes and maps of the world, you
can see lines of longitude (or parallels) and
lines of latitude (also known as meridians);
these imaginary lines help us to locate
different places on the Earth more easily.
The most important line of longitude is
the Prime Meridian which is located at 0°
longitude. It passes through Greenwich,
and is sometimes known as the Greenwich
Meridian. The most important line of
latitude is the Equator, which is located at 0°
latitude. The Equator divides the Earth into
the Northern and Southern hemispheres.
We measure the latitude of a specific place
on the Earth, depending on whether it is
North or South of the Equator; longitude
is measured in terms of East or West,
depending on whether the place is East or
West of the Prime Meridian. For example,
Mount Everest is located at 28°N (North
of the Equator) and 87°E (East of the
Prime Meridian).
North Pole
North
(latitude)
70°
60°
50°
40°
30°
20°
10°
0°
0°
10°
20°
30°
40°
50°
60°
70°
South
(latitude)
South Pole
Parallels are lines of longitude.
15°
30°
45°
60°
0°
15°
30°
45°
60°
75°
75°
Greenwich
Meridian
West (longitude)
East (longitude)
Meridians are lines of latitude.
1 W
hat is the difference between a world map and a globe?
10
90° 80°
Equator
You can also see the North Pole and South
Pole, which are the points we can imagine
the Earth’s axis passes through. If you look
at a globe, you will notice that the globe
is mounted on another imaginary line: its
tilted axis which simulates the real-life
tilting rotation of the Earth.
2 How are parallels and meridians different?
80° 90°
1
Unit
Maps
• Physical maps show the physical features of an area, such
as mountains, rivers, and lakes.
• P
olitical maps show state and national boundaries, as
well as important cities.
• Thematic maps show information on a particular topic.
There are many different kinds of thematic maps.
IB
NORTHERN
D u e ro
P Y
R E N
E E S
E
SUB-PLATEA U
E
CENTRAL SYST
M
T a jo
br
o
EM
ST
SY
SO U THER N
Gu
a
SUB- P L AT EAU
M O R E N A NGE
RRA
ir
RA
S I E alq uiv
C
d
TI
AE
B B PENIBAETIC
U
RANGE
S
There are three main types of maps:
CANTABRIAN
MOUNTAINS
N
IA
ER
A map is a representation of the Earth’s surface, which
shows how landmarks or monuments are related to each
other by distance, direction, and size.
a
Cantabrian Sea
AT L A N T I C O C E A N
Track 9
Types of maps
rr
te
Me di
le
Ba
an
ds
an
Isl
ic
ar
n
ea
Se
physical map
United
a
b
Norway
Estonia
Sweden
Russia
Latvia
Denmark
Lithuania
Ireland Kingdom
Belarus
BERLIN
Nether.
LONDON
Poland
Germany
Belgium
Ukraine
Lux. Czech Rep.
PARIS
Slovakia Moldova
France
Austria Hung.
Switzerland
Romania
Liech. Slov.
Cro.
Mon.
S.M.
Bos. Ser.
And.
Bulgaria
Italy Mon.
Portugal Spain
ROME
Macedonia
V.C. Albania
MADRID
Greece
political map
Climate
1 W
hat is a map?
c
Ocean
Mountain
Continental
Subtropical
2 W
hich map (a-c) would you need to find information about...
Mediterranean
1 ... a country’s borders?
2 ... a country’s weather?
3 ... a country’s geography?
Track 10
thematic map
Types of plans
Plans
0
250
500 m
Plans are used to show the distribution or location of objects
in a space or to indicate where buildings or places are located.
Buildings
Parks
Public buildings
Fountains
Train
There are four main types of plans:
• O
rthogonal checkerboard plans are usually used in
cities, which have streets arranged in orderly, straight and
parallel lines.
• Radiocentric plans are used in cities or towns, which have
circular avenues or streets, which lead to a common point
in the city centre.
N
radiocentric plan
N
0
250
Buildings
Parks
Public buildings
River
Train
500 m
• Linear plans show elongated places, usually near
motorways or main roads.
linear plan
N
• Irregular plans usually show smaller towns or villages
which do not have a definite structure.
1 a ) What are plans used for?
b) Which plan shows a town close to a motorway?
0
100
Buildings
Parks
Public buildings
River
Wall
200 m
irregular plan
11
Apply
your skills
Project
A solar eclipse
A solar eclipse happens when the Moon passes between the Earth and
the Sun, covering the light from the Sun. As we have seen, the Moon is
much smaller than the Sun, so how can the Moon cover the Sun?
Step 1
ake a ball of modelling clay and stick a pencil in it. Fix the
M
pencil to some modelling clay on the table, this represents
the Sun. Take a smaller ball of modelling clay and fix it to
the top of a pencil. This represents the Moon.
Step 2
lace the Moon in front of the Sun. It is much smaller, does
P
it cover the Sun?
Step 3
ow, slowly move the Moon away from the Sun towards
N
your face until you cannot see the Sun. The Moon now
covers the Sun. Has the Moon gotten bigger?
he Sun is about 150 million kilometres away but the Moon is only
T
384 400 kilometres away. Because the Moon is so much closer to us,
it looks like it covers the Sun, even though the Sun is much larger.
Penumbra
Umbra
The Sun
Earth
Night-time
Sun’s rays
The Moon
Moon’s orbit
HOW A TOTAL ECLIPSE OCCURS
12
Check what
you know!
k
Work in your noteboo
1 Put the planets in order, based on their distance from
the Sun.
2 Match the space words with their descriptions in your
notebook.
1 comet a) T
he areas where millions of stars
and nebulae group together.
2 planet
b) An object that moves around a
larger object e.g. the Moon.
3 star
c ) A large ball of ice and rock.
4 galaxy
d) A sphere made of rock or gas
that orbits a star e.g. the Earth.
5 satellite
e) A sphere of hot, glowing gas.
3 Why do we have seasons? Choose the correct answer.
a) Because the Moon orbits the Earth.
b) Because the Earth rotates.
c ) Because the Earth is tilted.
4 How many days does it take for the Earth to orbit
the Sun?
opy and complete the sentence about the seasons.
5 C
When the North Pole is tilting towards the Sun, during
its orbit, it is … in the Northern Hemisphere and … in
the Southern Hemisphere.
ame the different layers of the atmosphere.
6 N
7
Draw and label a sketch of the geosphere.
8
an you name all of the Earth’s continents?
C
(Hint: there are six).
My Word list
asteroid (belt)
atmosphere*
axis (of rotation)
comet
dwarf planet
eclipse
Equator
equinox
galaxy
geosphere**
globe
hemisphere (Northern
and Southern)
hydrosphere
landforms
latitude
light years
longitude
map
meridians
meteorite
Milky Way (the)
Moon (the)
nebulae
orbit
parallels
plan
planet
planetary system
Poles (North and
South)
Prime Meridian
rotate
satellite
solar system
solstice
star
Sun (the)
tectonic plates
universe
*For more vocabulary related to the atmosphere, look on page 8.
**For more vocabulary related to the geosphere, look on page 7.
13