Transcript Solar System Presentation Inner Planets

Meteors and Comets
What is a planet?
The Planet Test
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planet must be nearly round
 A planet must orbit a central star
 A planet has to be big enough to
have cleared out its orbit of other
objects
How do planets move?
Keplar’s First Law of Motion
All planets move in an elliptical
orbits having the sun as one
focus. (Law of Orbits)
Comets
Comets are made out of dust and ice
 Comets come from the Kuiper Belt and the
Oort Cloud
 A comet’s coma, or tail can be behind it or
in front of it
 Comets are like frozen snowballs
 Comets look like asteroids except for the
tail
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Comets
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Scientists try to predict when comets will come too close
to Earth
Sometimes comets collide with planets and their moons
Haley’s Comet is the most famous comet, it passes by
Earth every 76 years – the last time it passed by Earth
was in 1986
When Earth crosses the path of a comet, leftover dust
and ice can create increased numbers of meteors in
what's known as a meteor shower.
Comets
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They travel around the Sun in an orbit.
Are warmed up as they approach the Sun. This causes
the Comet to form a head and tail. The head is the
cloud-like mass we see in the front. The tail is the trailing
part which is made up of small particles and ice.
Are usually named after the person who discovered
them.
Halley's Comet (above) and Hale-Bopp Comet (right) are
two famous comets.
Meteors
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A meteoroid is a small particle from a comet
or asteroid
A meteor is much smaller than an asteroid
When a meteor hits the ground its called a
meteorite
A meteor is the streak of light from the
meteoroid
Meteors
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38,000 meteorites have been found on Earth so
far, from all over the world, but most are found in
the hot desert or in freezing cold Antarctica
There are three main types of meteorites: stony,
iron and stony-iron
Meteors enter the Earth's atmosphere on a
regular basis
The End
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What are comets made of?
Where in space are comets formed?
What is the MOST famous comet? How often
does this comet pass by Earth?
How are meteor showers formed?
What is a meteor?
How are comets and meteors DIFFERENT?
What are the three main types of meteorites?
Where do most meteorites fall on Earth?