# How would the transfer of mass from the Moon to Earth change the rotation, orbit and speed of the Moon and Earth?

I've read the creation of dams in Earth can change the speed of rotation of the planet because they reallocate the mass over the planet.

Let's suppose humans find a valuable mineral in the Moon and they start to transfer it in huge amounts to the Earth. How would the massive transfer of mass from the Moon to Earth, change the rotation, orbit and speed of the Moon and Earth.

Ok, so since possible repliers have been how much mass it would transfers, let's suppose I want to know the effects from any point between 0 to 1/10 to the mass of the moon. Since the effects would be different when 1% was transfered to the point to when 10% was transfered

• What is "massive" for you? This is quite important if the question is to be answered quantitatively. A thousand tons, a million tons, a billion tons, ten thousand trillion tons? If the last value seems "massive" to you, please be aware that it represents just a little more than 0.01% of the mass of the Moon... – AlexP Oct 3 '18 at 12:23
• I think you need to be more specific about how you plan to move this mass to the earth from the moon. This is important so that we can talk about where the energy comes from as well as where it goes. – Mathaddict Oct 3 '18 at 22:41
• @Mathaddict: Energy is not a conserved quantity in mechanics. On the other hand, momentum is... – AlexP Oct 4 '18 at 10:34
• @AlexP, is it your assertion then that energy cannot affect momentum? – Mathaddict Oct 4 '18 at 13:51
• @Mathaddict: Energy can obviously affect momentum, or else engines won't turn... – AlexP Oct 4 '18 at 14:19