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Is the Earth loosing weight?

  1. Mar 23, 2010 #1
    i was curious wether the earth is decreasing in mass, as we humans are converting much off this mass into energy i.e. burning of fossil fuels etc..., in which we are using up natural resources quicker than they can be replenished.
     
  2. jcsd
  3. Mar 23, 2010 #2

    ideasrule

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    In any chemical reaction, including combustion of fossil fuels, the mass of the products is almost exactly equal to the mass of the reactants. The only mass lost--and this mass is utterly negligible--is due to the energy produced, which carries away m=E/c^2 of mass.
     
  4. Mar 23, 2010 #3

    Lok

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    The earth receives more energy out of space in one day, than we use in one year (moderate exageration). Our use does not send the energy out into space either so you cannot say it is lost.

    Plus look on the internet of the average mass of dust and meteorites that land on our planet, and you will find that the mere kilograms of energy we use (and don't loose) are really insignificant to the tonnes ( many zeroes) that we gain. The earth is getting heavier, fat, chuncky.
     
  5. Mar 23, 2010 #4

    Lok

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    Even so the mass (total mass of system) does not shrink unless that energy leaves the system, which in our case is the earth. The concept that mass transforms into energy and stops attracting other things through gravity is so common, that I wonder where so much misunderstanding comes from.
     
    Last edited: Mar 23, 2010
  6. Mar 23, 2010 #5
    Um.. I guess I didn't delete that post fast enough. Oh my.

    I'm not so sure that what you say isn't what ideasrule has said.
     
  7. Mar 23, 2010 #6

    Lok

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    I edited mine ... And expecting a beer :P
     
  8. Mar 23, 2010 #7
    I think, somehow, you only added a new one. I'll buy you a rootbeer.
     
  9. Mar 23, 2010 #8

    Lok

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    The info is still valid, we'll just never know what was said :P.

    Cheers!!!
     
  10. Mar 23, 2010 #9

    mgb_phys

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    The atmosphere loses about 3kg of Hydrogen and 0.05kg of Helium per second - from just thermal motion.
    It gains about 1500kg/s of meteors/comet fragments etc (100,000 tons/day)

    Solar wind stripping isn't significant because of our magnetosphere - it probably deposits more protons (into H) than it removes.
     
  11. Mar 23, 2010 #10

    mgb_phys

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    The moon probably lost any atmosphere just from lack of gravity, it doesn't take much for a molecule to achieve escape velocity on the moon.
    Estimates are that the even Earth would lose it's atmosphere in 3Bn years if it wasn't replenished by volcanoes.

    Mars probably lost it's atmosphere to solar wind stripping. It's just small enough that it doesn't have a molten core so no magnetic field so no protection.
    Venus should have lost it's atmosphere to solar wind but probably produces so much from volcanics activity that it makes up for it.
     
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