Download Space Part1

Introducing the Solar System
The Solar System is made up
of various celestial objects:
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the Sun
the planets
moons
asteroids
comets.
How do these objects interact?
The Sun is a star – a massive ball of hot glowing gas.
It has the strongest gravitational field in the Solar System.
All the other celestial bodies orbit around it.
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The rotation of the Earth
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The path of the sun in the sky
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What are hemispheres?
The Earth is divided into two hemispheres, separated by
the equator.
northern
hemisphere
equator
southern
hemisphere
Why do the hemispheres have different seasons at
different times of the year?
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The seasons
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What is the season?
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The Moon
The Sun and the Moon look about the same size from
Earth, but they are not.
The Sun is about 400 times wider than the Moon but is
400 times further away!
sunlight
The Moon takes just over 27 days to orbit the Earth.
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The phases of the Moon
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Phases of the Moon activity
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Questions about the Moon
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Eclipses
A solar eclipse happens when
the Moon passes between the
Sun and the Earth, casting a
shadow over the Earth.
The last solar eclipse over the
UK was on 11th August 1999.
They are rare in the UK.
A lunar eclipse happens when
the Earth passes between the
Sun and the Moon, casting a
shadow over the Moon.
Lunar eclipses happen in
most years.
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What happens during a solar eclipse?
Where must the Moon be for a solar eclipse to take place?
During a solar eclipse the Moon moves directly between
the Sun and the Earth, blocking the Sun’s rays from
reaching part of the Earth.
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What happens during a lunar eclipse?
Where must the Moon be for a lunar eclipse to take place?
During a lunar eclipse the Moon is on the opposite side
of the Earth to the Sun, blocking the Sun’s light from
reaching the Moon.
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Questions about eclipses
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Gravity and satellites
A satellite is any object that orbits another object.
The Moon is a natural satellite of the Earth and is kept in
orbit by the attraction of the Earth’s gravity and by its motion.
An artificial satellite is
an object made by, and
put into orbit by, humans.
Why do you think satellites
stay in orbit, instead of
falling back onto the
surface of the Earth or
drifting off into space?
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Newton’s thought experiment
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