Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: thedoc on 24/10/2014 16:30:01

Title: Can we increase gravity on the earth by increasing its mass?
Post by: thedoc on 24/10/2014 16:30:01
Joshua asked the Naked Scientists:
   
Can we increase the force of gravity on the earth by increasing its mass. Let's say by knocking asteroids into our oceans? If the above is true would the orbit of the moon be affected?

What do you think?
Title: Re: Can we increase gravity on the earth by increasing its mass?
Post by: chiralSPO on 24/10/2014 17:02:12
The Earth has a mass of 5.97x1024 kg. You would have to increase that by 1% (5.97x1022 kg) to get a 1% increase in the gravitational attraction to the moon. Introducing this much mass by way of meteorite impact would probably kill everything on the Earth many times over. But in theory, yes we could increase the mass of the Earth and it would change the moon's orbit.
Title: Re: Can we increase gravity on the earth by increasing its mass?
Post by: lightarrow on 24/10/2014 20:32:50
The Earth has a mass of 5.97x1024 kg. You would have to increase that by 1% (5.97x1022 kg) to get a 1% increase in the gravitational attraction to the moon. Introducing this much mass by way of meteorite impact would probably kill everything on the Earth many times over. But in theory, yes we could increase the mass of the Earth and it would change the moon's orbit.
or we could put a 100 metres large sphere of neutron star's material at the centre of Earth 😊.
I don't take responsibility for the subsequent tidal forces near that sphere, anyway 😊

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lightarrow

Title: Re: Can we increase gravity on the earth by increasing its mass?
Post by: PmbPhy on 24/10/2014 22:04:03
Quote from: chiralSPO
Introducing this much mass by way of meteorite impact would probably kill everything on the Earth many times over.
A super advanced civilization might be able to slow the asteroid down before placing it on earth. But where to put it so that it wouldn't cause a problem is a serious issue.
Title: Re: Can we increase gravity on the earth by increasing its mass?
Post by: chiralSPO on 24/10/2014 22:36:51
Perhaps an advanced civilization could use a space elevator that can convert the asteroids potential energy into useful work as it is lowered at a safe velocity...