1 of 48© boardworks ltd 2008 introducing the solar system how do these objects interact? the solar...
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1 of 48 © Boardworks Ltd 2008
Introducing the Solar System
How do these objects interact?
The Solar System is made up of various celestial objects:
the Sun the planets moons asteroids comets.
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.
northernhemisphere
equator
southernhemisphere
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 Sun and the Moon look about the same size from Earth, but they are not.
The Moon
The Moon takes just over 27 days to orbit the Earth.
The Sun is about 400 times wider than the Moon but is 400 times further away!
sun
lig
ht
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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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A solar eclipse happens when the Moon passes between the Sun and the Earth, casting a shadow over the Earth.
Eclipses
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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Where must the Moon be for a solar eclipse to take place?
What happens during a solar eclipse?
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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Where must the Moon be for a lunar eclipse to take place?
What happens during a lunar eclipse?
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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An artificial satellite is an object made by, and put into orbit by, humans.
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.
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