Surface tension causes liquids in microgravity to form perfectly round spheres.

In differential geometry, the Willmore energy is a quantitative measure of how much a given surface deviates from a round sphere.

A round sphere has zero Willmore energy.

Unlike the live-action film, it is in the shape of a round sphere, rather than a square cube.

He was towing a black, round sphere which slid along behind him.

For example, a round sphere evolves under IMCF by expanding outward uniformly at an exponentially growing rate (see below).

And, on average, the shapes still smudge into a round sphere, he said.

Shave away any cloudy ice and carve the block into a round sphere like a magnifying glass.

He also devised machinery to produce perfectly round spheres and a way to measure deviations in roundness within one-tenth of a millionth of an inch.

Examples include all round odd-dimensional spheres, and the product of a 2-sphere and a 3-sphere with a homogeneous metric.