Change in orbit due to moment of inertia change?

AI Thread Summary
The discussion centers on the impact of the Three Gorges Dam on Earth's moment of inertia, leading to a slight increase in the length of days by 60 nanoseconds. Participants express that this change will not affect Earth's orbit around the Sun, as it does not alter the planet's mass or its distance from the Sun. The negligible effect on tidal locking between Earth and the Sun is also noted, given the vast distance involved. Overall, the consensus is that while the change in day length is interesting, it has no significant implications for Earth's orbital dynamics. The conversation highlights the minimal physical effects of such changes on a planetary scale.
DrBwts
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Hi,

So recently I read about the massive 3 gorges dam changing the mass moment of inertia of the Earth to such an extent that the days will now be 60ns longer.

Then I thought, how will this effect the orbit of the Earth about the Sun?

Any thoughts?
 
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Wow! A whole 60 ns longer each day! Man, I can catch some additional zzzs every morning!

I wouldn't worry about any orbital changes w.r.t. the Earth's movement about the sun.

BTW, in 60 ns, a beam of light travels about 18 meters.

It would also take over 160 million years to add an additional HOUR to each day.
 
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DrBwts said:
Then I thought, how will this effect the orbit of the Earth about the Sun?
It won't. It hasn't changed the Earth's mass one iota, nor has it changed the distance between the Earth's center of mass and the Sun.
 
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what about tidal locking effects between the Earth and the sun? I guess it is negligibly small, since the size of the Earth and sun is very small compared to the distance between them.
 

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