I have asked this before and didnt get an answer?

Question

If the shape of an object is changed, does that change the shape of its gravitational field. or does a gravitational field always have to be spherical.

Answer 1

Gravitational field of any object is sperically symmetric at large distances from this object. 'Large' means distance is much larger than than the size of the object.

Near field, however, sharply depends on the details of mass distribution of the object. If, for example, you have thin masive disc, shaped like a coin, the gravitational filed near the surface will be perpendicular to the surface, and not in direction to the center of the disc..

Answer 2

Of course the gravitational field of an object depends on its shape. You can calculate the potential and force fields as a function of the density distribution of the object by solving a volume integral over the volume of the object.

The far field solution only depends on the total mass of the object and will always go like 1/r for the potential and 1/r^2 for the force. The near field solution, however, depends on the precise shape of the object.

Non-Newtonian gravity experiments like the physicists at Washington University:

http://www.npl.washington.edu/eotwash/experiments/experiments.html

make use of the shape dependent gravitational field to test the 1/r potential for gravitational interaction at short scales.
In some of their experiments these physicists use plates/rings with holes in them:

http://www.npl.washington.edu/eotwash/experiments/shortRange/sr.html

The special form of the gravitational field for these shapes is then used to predict the torsion between them. Any deviations of the measured torsion forces from the expected ones is a sign that gravity at short distances (<1mm) does not follow a 1/r law. These are very fundamental and important experiments.

Answer 3

As long as the centre of gravity of the object remains same (which may not be the case if the shape gets distorted too much), the gravitational field will remain same. If the centre of gravity shifts the gravitational field will change.

The gravitational field will remain spherical with respect to the centre of gravity (that means the gravitational field at that point on the sphere will be same).

Answer 4

it change the location of center of gravity. to find this center of gravity. clockwise moment is equal to counter-clockwise moment.