AI Art Placeholders
Terrestrial Moon
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Terrestrial Asteroid
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Terrestrial Comet
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Vulcanian Moon
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Vulcanian Asteroid
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Vulcanian Comet
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Cryogenic Moon
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Cryogenic Asteroid
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Cryogenic Comet
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Assets that could be used from opengameart.org
https://opengameart.org/content/2d-planets-0