Celestia

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Mostly written in C

License: al

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License: BSD-3-Clause, cc-by-3, gpl, lgpl21_or_later, Public_Domain

Gaia Sky   (Compare Project)

License: gpl3

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License: gpl3_or_later

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Sky Chart / Cartes du Ciel   (Compare Project)

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AllBinary Platform   (Compare Project)

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License: Unknown

Xith3D   (Compare Project)

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License: BSD-3-Clause

PixelLight   (Compare Project)

Mostly written in C++

License: mit