Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: thedoc on 03/04/2012 16:49:05

Title: Could Mining alter the Earth's Orbit?
Post by: thedoc on 03/04/2012 16:49:05

With all the millions of tons of material that is mined from the earth and redistributed around the globe is there a chance it could effect or alter the planet's orbit?

Andy from Folkestone

Asked by Andy Fletcher


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Title: Re: Can mining alter Earth's orbit?
Post by: CliffordK on 21/03/2012 12:39:38

As long as the material stays on Earth, it will  not affect Earth's orbit around the sun as the mass of Earth would remain unchanged.  Even moving it into the atmosphere doesn't affect the overall mass of the planet.  Moving material from one location to another, or from below the surface into the atmosphere could potentially affect Earth's spin, but the amount of material we mine is a tiny fraction of the weight of the Earth.

Consider the Earth weighs about
6×10²⁴ kg.

Consider the Fossil fuels.  Each year, about 9 gigatons (9×10¹²kg) of fossil fuels are mined and burnt. 

That means that we are mining and redistributing on the order of of the earth, or on the order of ten nanograms per kilogram.  And, remember, this material isn't lost, it is just moved.

We do, in fact, make the earth lighter by sending probes to distant planets.  However, this gets lost in the noise of weight gains from meteoroids, and solar wind, and weight loss from hydrogen escape, and particles being ejected by the solar wind.