A Group of Circular Orbs With Clear Structure

From the orbs photos we collected at present, we found the orbs are various. It can be said that every time the structure and color of the orb is different. Of course, some orbs are also similar, and the following is examples.
1. the similar orbs list (observe the photos):

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2. Analysis:
These orbs are similar: round in shape, with three layers, and the inner layer looks like an outstanding building.
These orbs are non-transparent, but it is easier for us to imagine their 3D figure.