Maybe the 1mm of dust and the cooling cancel each other.

 

Another interesting question ... but the earth won't lose or gain mass because of that ...

Actually, it does. The nuclear fission reactions in the core cause the loss of about 16 metric tons of mass every year.

 

Interesting thought... but did you know that between 30,000 to 100,000 tons of meteorites hit earth each year? The earth might as well be gaining mass, rather than losing it.

But this is more than offset by the hydrogen and helium that escapes into space every year.

 

But the days will get shorter.

If there's weren't other forces at play, but the tidal forces are slowing the Earth's rotation down. Eventually the same side of the Earth will always face the moon, just as we have already locked the moon's rotation to it's orbit about the Earth.

 

Actually, it does. The nuclear fission reactions in the core cause the loss of about 16 metric tons of mass every year.

Yeah... I had forgotten about that ... imagine that, 16 metric tons of mass converted into pure energy each year here on earth!

 

All gravitational orbits and spins are increasing. The gravitational constant is not constant. It's decaying. Because density is decreasing. Gravity is not fundamental....it depends on density. The weakest force is a by-product of an electrical asymmetric particle bond.

 

All gravitational orbits and spins are increasing. The gravitational constant is not constant. It's decaying. Because density is decreasing. Gravity is not fundamental....it depends on density. The weakest force is a by-product of an electrical asymmetric particle bond.

Apparently (!) it is a lot weirder than that. How about up and down following a 5.9 year sine wave?
https://phys.org/news/2015-04-gravitational-constant-vary.html

 

You will find similar results for the decay constant also.

 

Is the atmosphere part of the Earth's mass?

 

Is the atmosphere part of the Earth's mass?

Yes.