Square field on sphere when getting light from an emission

I'm experiencing the same thing. Happens on capsules too. The "edges" of the square field rotate along with the objects.

Edit: I found the problem when I baked in the lighting from a directional light. The spheres have UV map overlap issues. The "square fields" you're seeing are actually each of the uv maps. The Unity sphere is represented by a cube that's been distorted. Those are the seams. To fix the problem, it is better to use a sphere brought in from outside unity. But you can alleviate it by increasing the resolution of the lightmap both on the sphere and in the general lighting settings.

Here are two posts related to this: https://docs.unity3d.com/Manual/ProgressiveLightmapper-UVOverlap.html https://answers.unity.com/questions/1441500/sphere-uv-distortion.html