WHY ARE STARS & PLANETS ALWAYS SPHERICAL?

All planets we know may it be rocky or gaseous, all are roughly spherical in shape as we observe. The reason for this is gravity, in an object the center of gravity is concentrated at the center of it. The larger an object is, more is its self-gravitation.

This gravity tries to form the most efficient shape possible by creating a pull towards the center of mass in all directions. The most efficient shape is a sphere.

If an object is small in size, the atomic forces and bonds they contain overcome the gravitational force as gravity is the weakest force we know of and hence they are able to retain their original shape. This is the reason that the objects we see everyday are present in their original shape.

A perfect sphere is very rare to see but with time the heavy massed objects tend towards becoming closest shape to sphere.

Let me know if such questions come to your mind too :)