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This is a paid asset, but we’ll share Spherical Skybox Pack Free for you. Enjoy!!!
Spherical Skybox Pack v1.0
This package contains 10 spherical skyboxes. These skyboxes have a panorama view, and they can be seen in every direction. You can use them as a background of a small planet, for various scenes. All textures are in PNG format, with 2048×2048 max size. There is also a demo scene of a small planet, with a simple gravitational system.