Why are many things in the universe round?

Question

Take a walk outside and you'll realise many things are round. Wheels are round, a cup is round and even that home button on your iPhone is round. But that's all man made.

In nature, there are many things that are round too! From the planets to our sun and even a sunflower or atom. They are all round. Well, they might not be a perfect circle but they all take that round, curved shape. The universe seems to take this circular approach to almost everything. This doesn't only include objects but concepts too, including orbits, spirals, and rotation.

From my experience, creating round things is often much easier than creating things with edges. For example, when building a snowball it is much easier to mould the snowball into a sphere than a cube. Could this be a reason to why the objects in our universe are so round.

Why is it that almost everything in the universe is based upon round things?

Answer 1

For large massive objects, planets upwards say, it is because of gravity.

For smaller objects it can often be attributed to minimisation of potential energy, as example of this is shown by objects such as soap bubbles.

Also the ratio of surface area to volume will favor spherical shapes in biological systems.

For inorganic objects, such as pebbles on the beach, wear will tend to reduce the "sticky out" bits and rough edges, especially if the object can revolve and be worn away by both weathering forces such as sea and air, as well as the objects surrounding it.

Answer 2

for biological systems like the spherical nature of your eyeballs, red blood cells or the lipid bi-layer of cellular membrane etc.; it is the difference between two systems i.e the outer disorganized(entropy) system versus the inner more organized system(enthalpy) that keeps them spherical.