High School Do planets without a solid surface precess?

[metastable]

Do black holes precess? I added some marks to a picture of quasar 3c175... can the highlighted distortion of the jet be interpreted as black hole precession?

 

[.Scott]

Precession will occur when an external force applies angular momentum to a spinning object that is not aligned with that objects spin axis. Accretion disks are, in general, not aligned exactly with the black holes spin axis - but the material becomes aligned before it nears the even horizon.

This process was modeled in a study just released this month:
https://academic.oup.com/mnras/article/487/1/550/5420428
(suggest you skip to "RESULTS")

According to the authors, the acretion disk does "torque" the black hole. So it would seem inevitable that the black holes spin axis would precess.

 

[metastable]

Very interesting. I was reading about axial precession on the Earth:

For precession, this tidal force can be grouped into two forces which only act on the equatorial bulge outside of a mean spherical radius. This couplecan be decomposed into two pairs of components, one pair parallel to Earth's equatorial plane toward and away from the perturbing body which cancel each other out, and another pair parallel to Earth's rotational axis, both toward the ecliptic plane.[20] The latter pair of forces creates the following torquevector on Earth's equatorial bulge:[4]

https://en.wikipedia.org/wiki/Axial_precession

If I understand correctly, the Earth requires non-spherical asymmetry for its precession to occur, is a black hole thought to be the same in this regard?

 

[Ibix]

A spinning black hole is not spherically symmetric, no. A non-rotating one is.

Don't assume precession of a black hole has anything to do with forces, though. Gravity is not a force in general relativity.

 

[hmmm27]

The pic in colour and NASA description

Would a gaseous or liquid planet also precess ? there being no cohesive structure to tilt.