Re: Question, what do things do when they freeze?


"Wiley Coyote" <nospam@xxxxxxxxxxxxx> wrote in message
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"George" <george@xxxxxxxxxxxxxxx> wrote:
"Wiley Coyote" <nospam@xxxxxxxxxxxxx> wrote in message
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There are a couple of misconception that I would like to clear up:

First- the earth isn't a perfect sphere (over and above variations in
the
surface). It flattens at the poles slightly and is a tad fatter at the
equator. The equatorial radius is 6,378,140m and the polar radius is
6,356,755m which gives the earth a 21.39km sag around the middle. (1)

This is a pretty good indicator that the earth isn't a monolithic
solid.



Second: In the strictest sense, the process of accretion is ongoing.
Every day
the earth recieves a few tons of dust from interplanetary space. This
dust is
mostly microscopic- carbon or silicon based. On a daily basis, the
amount
is
negliable but it can add up over time. This dust is regulary
replenished
by
the occassional comet.

It adds up to very little of the overall mass of the earth.

George


True enough. A few tons of dust a day is a mere nuisance. Like continents
that
move mere fractions of an inch per year-- over time it adds up.

Every year nearly 40,000 tons of microscopic particles from asteroid
collisions or passing comets rain down on the Earth. Much of this
extraterrestrial debris is vaporized or melted in the atmosphere. Only a
tiny amount of dust - mainly particles no bigger than the width of a human
hair-- survives entry, much of it settling to the bottom of oceans and
lakes or is trapped in ice. If there were significant amounts contributing
to the huge volume of the earth, we'd see substantially larger amounts of
it in the Antarctic ice cores than we actually find.

George


.

Relevant Pages

  • Cosmic Dust in Ice Cores Sheds Light on Earths Past Climate
    ... Earth Institute News ... Cosmic Dust in Ice Cores Sheds Light on Earth's Past Climate ...
    (sci.space.news)
  • Re: Where Matter Comes from For Planetary Growth
    ... The earth is growing! ... The total weight of this dust is about 4 million ... at night and scavenge dead skin from your face. ... You have more bacterial cells than human ...
    (talk.origins)
  • Re: Where Matter Comes from For Planetary Growth
    ... The earth is growing! ... The total weight of this dust is about 4 million ... You have more bacterial cells than human ... bacterial cells outnumber your own cells by a factor of about 100 to 1. ...
    (talk.origins)
  • Re: Where Matter Comes from For Planetary Growth
    ... The earth is growing! ... The total weight of this dust is about 4 million ... You have more bacterial cells than human ... bacterial cells outnumber your own cells by a factor of about 100 to 1. ...
    (talk.origins)
  • Re: Global Cooling
    ... would also like to know for how long each month these trajectories ... I?m interested to see if Moon dust could be used to reduce sunlight ... reaching Earth in the event that global warming is not controlled. ... you will need some 53 million metric tons. ...
    (sci.space.tech)