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Q & A: Do asteroids hit the earth?

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Most recent answer: 03/13/2015
Q:
Hi.This is a physics and planetary question/puzzle.It has always interested me how the earth remains relatively unscathed given the ammount of asteroids and such that have collided wih all the planets in our solar system over eons of time. The moon is heaverly cratered.It occured to me that may be the particular positions and orbits of the other planets around the sun are such that they act like a protective barrier to the planet earth with respect to incoming asteriods etc.Which has allowed life as we know it to develope on our planet.Think of the solar system like you would the structure of an atom. An atoms particals are spread very far apart orbiting at [enourmous speeds] round a central nucleus. So fast that the atom is in effect almost a solid object even with all the empty space thats makes up the atoms.Think of it also like this......Poke a stick through a farmers cartwheel and it will penetrate ok. But rotate that cartwheel at eg.20000 reves per minute and you cannot poke your stick through the spokes. The rotating wheel has in effect become a solid.The whole point of all this to try and find out if the planets in our solar system have acted like a protective barrier to the earth.One way to test this is to creat a computer animation of the solor system and speed there orbital motions up ensuring that each planet leaves a trail behind it so you can see if a protective shell builds up as asteroids etc travel inwards.With the planetary orbits being a known quantityit may even be possible to do some predictive testing just like the weather people do when anylising weather conditions into the future.If nothing is shown to prove anything then thats ok.But if there is evidence of a protective nature thenthis may have implications for the theory that existance and ourselves are no accident of nature and is some how organised.So if any student [computer programmer] wants to take up the challenge to animated a solar system in the way ive suggested and see what happens then i look foreward to knowing the outcome.Thanks for any info/comments in reply.Regards KEN.
- Kenneth Rushforth (age 65)
Birkenhead Wirral England
A:

Hello Kenneth,

I think your premise is incorrect. According to    small asteroids near Earth, with sizes of only about a meter, hit the atmosphere and disintegrate with surprising frequency - around every other week.  Here is a ten year scatter plot of impacts:

Map showing the bolide events from 1994 to 2013

There is evidence for a catastrophic asteroid hit 65 million years that killed off some three-quarters of plant and animal species on earth —including almost all of the dinosaurs. .

LeeH


(published on 03/13/2015)

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