the earth and moon tilted earth day and night the seasons satellites phases of the moon
TRANSCRIPT
The Earth and Moon
Tilted Earth
Day and night
The seasons
Satellites
Phases of the Moon
The Earth
It is covered by 70% WATER and 30% LAND.
We live on a PLANET called EARTH. It is the only planet we know that has LIFE.
It also has two PERMANENT ICECAPS at the NORTH POLE and the SOUTH POLE.
It is surrounded by a mixture of gases called the ATMOSPHERE. The atmosphere consists mostly of NITROGEN and OXYGEN.
What do you notice about the diagram of the Earth above?
The Earth is TILTED on its AXIS.
Exercise 1: The Earth
1. What percentage of the Earth is land?
2. What do we call the layers of gas that surround the Earth?
3. What is unusual about the Earth?
4. Which two gases make up most of the Earth’s layers of gases?
5. Which gas is required for respiration?
30%.
The atmosphere.
It is tilted upon its axis and it is the only planet that supports life.
Nitrogen and oxygen.
Oxygen.
Length of Year
The time it takes the Earth to ORBIT (move around) the Sun ONCE is called a YEAR. It takes 365.25 days for the Earth to orbit the Sun once.
Earth
Sun
The SeasonsThe AXIS is an IMAGINARY LINE that runs through the Earth. The Earth is TILTED on its axis at an angle of 23º.
The Earth’s tilt causes the SEASONS.
When the northern hemisphere is tilted towards the Sun, it is northern summer and winter in the southern hemisphere.
When the southern hemisphere is tilted towards the Sun, it is southern summer and winter in the northern hemisphere.
Summer and Winter
Sun in WINTER at noon.
Sun in SUMMER at noon.
When is the Sun highest in the sky? Summer or winter?
Why?Why is it northern summer when the northern hemisphere is tilted towards the Sun?
When the northern hemisphere is tilted towards the Sun, the Sun is at a higher angle in the sky and the Sun’s rays are less spread out. Therefore, they have a greater heating effect. In northern winter the Sun is at a lower angle in the sky because the northern hemisphere is tilted away from the Sun. Consequently, the Sun’s rays are more spread out and have a lower heating effect than in summer.
Day and NightThe Earth SPINS on its axis once every 24 HOURS. The time it takes a planet to spin once on its axis is the length of that planet’s DAY.
Where on the diagram below is it daytime?
Night time?
Sunrise?
East and West
The Sun RISES in the EAST.
Because the Earth SPINS, the Sun moves across the sky.
NOON is when the Sun is HIGHEST in the sky.
The Sun SETS in the WEST.
How does the Sun move across the sky during the day?
Length of Day
The Sun is at a higher angle in the sky in summer than in winter. This means that the Sun is ABOVE THE
HORIZON longer in summer than in winter. So, in summer, the days are longer and the nights are
shorter, compared to winter.
Exercise 2: The Sun
1. Why does the Sun appear to move across the sky?
2. In which direction does the Sun rise?
3. In which direction does the Sun set?
4. When is the Sun at its highest angle in the sky, winter at noon or spring at noon?
5. When is the Sun at its lowest angle in the sky, summer at noon or autumn at noon?
The Earth spins on its axis.
In the east.
In the west.
Spring at noon.
Autumn at noon.
Exercise 3: Fill in the Key Words
When the Sun is at its highest _____ in the sky we call it the summer _______. This is when it is the _______ night (and longest day).
When the Sun is at its lowest angle in the sky we call it the _____ solstice. This is when it is the longest night (and shortest day).
There are two days when the length of day and night are the same; these are called the autumn and spring ________.
equinox angle winter solstice shortest
anglesolstice
shortest
winter
equinox
Exercise 4: Link the Word with the Description
Shortest day of the year.
An imaginary line that runs through the Earth.
Longest day of the year.
When the length of day and night are the same.
Caused by the Earth’s tilt.
The time it takes the Earth to rotate once.
Axis
Seasons
24 hours
Equinox
Summer solstice
Winter solstice
Exercise 5: The Earth
1. What is the summer solstice?
2. How many equinox are there?
3. Where on Earth do they have 24 hour days and 24 hour nights?
4. What causes the seasons?
5. What causes day and night?
When the Sun is at the highest angle in the sky (Longest day, shortest night).
Two (spring and autumn).
The North Pole and the South Pole.
The Earth being tilted (at an angle of 23°).
The Earth rotating once every 24 hours.
Exercise 6: Day and Night
1. For the diagram below, which letter represents somewhere where it is…..
a) Sunrise
b) Sunset
c) Is it showing northern summer or northern winter?
A
E
SatellitesSATELLITES are objects that ORBIT other BODIES.
Satellites are held in orbit by the FORCE OF GRAVITY of the body they are ORBITTING.
Gravity is the FORCE OF ATTRACTION between all MASSES. The LARGER THE MASS, the greater the attraction. The CLOSER two masses are together, the greater the attraction.
ARTIFICIAL SATELLITES are satellites that are made by humans. They have many uses:
ASTRONOMY
GEOLOGY
COMMUNICATIONS
STUDYING CLIMATE CHANGE
MONITORING THE WEATHER
The MoonThe MOON is the Earth’s nearest neighbour. It is a NATURAL SATELLITE of the EARTH.
The Moon has NO ATMOSPHERE or liquid surface water. Its surface is covered in CRATERS made by impacting asteroids.
Several manned missions have been to the surface of the Moon and it is the only other surface that humans have walked on.
The Moon is seen by REFLECTED LIGHT and it takes 28 DAYS to ORBIT the Earth.
Phases of the Moon
A B C D E F G H
New Moon
Full Moon
The View from Earth
Exercise 7: Link the Word with the Description
When the near side of the Moon is fully illuminated
The force of attraction between all masses
To move around a body in a path
When the far side of the Moon is fully illuminated
Natural satellite of the Earth
A use of artificial satellites
Gravity
The Moon
Weather monitoring
New Moon
Full Moon
Orbit
Exercise 8: Satellites
1. What is a satellite?
2. What force keeps the Moon in orbit around the Earth?
3. What is an artificial satellite?
4. Give three examples of the uses of artificial satellites.
5. How long does it take for the Moon to orbit the Earth?
A body that orbits another body.
Gravity.
A human-made satellite.
Weather, communications, geology, astronomy, monitoring climate change, military.
About 27.3 days.
Exercise 9: Imagine…Imagine that you are out one day and all of a sudden the Sun disappears. What would happen? What would be the effect for life on Earth? Write a short essay describing what you think would happen (and why). Jot some ideas down at the back of your book before you start.