Earth’s inner core is growing unevenly. Why isn’t the planet tipping?

Look, I’m from the government and I’d like to remind you all that the mole people are just a myth. We have mining regulations to save lives, except not from the mole men. Let’s say it’s for safety. Anyway, you should trust the government.

Generally the variation in gravitational field is so weak it doesn’t do much except add errors to data. It’s more efficient to launch satellites near the equator, but that’s not because of the Earth’s bulge or gravity, but rather the big radial velocity down there.

If I could only get a ride to the hole at one of the poles I'd be happy to go visit the mole people. I also heard a rumor that they're suing Australia over the use of "down under".

There can be interesting impacts on orbiting satellites - mostly gravity irregularities just add stationkeeping work, but they can sometime be leveraged to alter a satellite’s orbital inclination (a plane change). For Lunar orbit they’re even more of a consideration, in addition to Earth’s gravity effect on lunar satellites.

https://science.nasa.gov/science-news/science-at-nasa/2006/3...

I thought they were reptilian?

The relativistic effects are negligible.

The Sun and the Moon have a big enough impact to make the our planet spin, orbit the Sun, cause tides, etc.

Tilt is with respect to our orbit around the sun and apparently mostly the moon is to blame for the tilt.

https://www.obliquity.com/info/meaning.html

I don't think it's gravity as that is well measured to the scale of nm/s^2 and any external localized field distortion would have been measured.

If I have to guess, it would be that the below Indonesia (where the bulge is according to the article) there is more radiative cooling happening either due to a thinner crust or higher concentration of more thermally conductive elements in the inner and outer core/mantle/crust. These effects can be localized because the soup from which the Earths' insides were made was "liquid" to a point and so an even mix of elements is highly unlikely even after accounting for billions of years of gravitational differentiation. For example, the outer core is the only technically liquid part and it still has an incredibly high viscosity (1000s to billions of times the viscosity of water [1]) and definitely you wouldn't call that a liquid in your day-to-day life.

[1] https://arxiv.org/abs/0709.3333

You don't necessarily need gravity to make something tilt, it can happen naturally during rotation. For instance, imagine spinning something that distorts asymmetrically, like a pencil with some silly putty attached to one side.

Alternatively, there's stuff like this: https://www.youtube.com/watch?v=1VPfZ_XzisU. Angular momentum's always conserved, but the axis of rotation might not be.

I think it's a good question. What deformations would we expect if the Earth had captured a very tiny black hole?

You may be on to something. It could be used as the world's greatest random number generator.

https://blog.cloudflare.com/randomness-101-lavarand-in-produ...