(P2) Threats to Earth.

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  • Created by: Anjelala
  • Created on: 20-05-13 19:48
What are asteroids?
> Asteroids are mini planets orbiting the sun
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Where do most asteroids orbit?
> Most asteroids orbit between Mars and Jupiter.
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Where did asteroids come from?
They are large rocks left over from the fomation id the Solar system.
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How were ALL bodies in space formed?
> ALL bodies in space were formed when clouds of gas and dust collapsed together due to gravitational forces of attraction
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What determines the gravitational force of an object?
> The objects mass determines on its graitational force.
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State a difference between the masses of asteroids and Jupiter....
>asteroids have relatively low masses compared to mass of Jupiter.
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How does Jupiter's gravitational force effect asteroids?
> Jupiter's gravitational force stops asteroids joining together to form another planet.
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What do scientists believe about the origin of the moon?
>They believe that the moon was a result of a collision between 2 planets in the same orbit. > The iron core of the other planet melted and joined with the earth's core > Less dense rocks negan to orbit and they joined together to form our moon.
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What evidence supports scientists' belif about the origin on the moon?
> Average density of Earth is 5500 kg/m3 while moon is only 3300 kg/m3 >No iron in the moon >Moon has same oxygen composition as the earth , but rocks on mars/meteorites have different oxygen composition.
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How do we know asteroids have collided with Earth?
> craters created as a result of an asteroid impact. > Quantities of metal > iridium found near craters > many fossils found below the layer of iridium, but few found above it.> tsunamis disturbes
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Where do most comets pass ?
>Most comets pass inside the orbit of Mercury and well beyon like pluto.
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What hppens to a comet as it comes closer to the sun?
> Ice melts and sloar winds blow the dust in to the comet's tai ( which always faces away from sun).
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What does NEOs stand for?
Near- earth object
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What happens to the speed of a comet as it goes near and goes away from the sun?
> Speed of comet increases when it goes near sun , speed decreases when it goes further away from sun due to changes in gravitational attraction.
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What could be done if an NEO is on a collision course with Earth ?
1 option would be to explode a rocket near the NEO which could alter its course enough to miss Earth.
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Other cards in this set

Card 2

Front

Where do most asteroids orbit?

Back

> Most asteroids orbit between Mars and Jupiter.

Card 3

Front

Where did asteroids come from?

Back

Preview of the front of card 3

Card 4

Front

How were ALL bodies in space formed?

Back

Preview of the front of card 4

Card 5

Front

What determines the gravitational force of an object?

Back

Preview of the front of card 5
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