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How did Aryabhata explain the apparent westward motion of the stars?
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Indian mathematics
The evolution of Hindu-Arabic numerals from Brahmi through Devanagari and Arabic to European scripts.
In the context of Indian mathematics and astronomy, the scholar Aryabhata provided a revolutionary explanation for the apparent westward motion of the stars.
In his treatise, the Aryabhatiya, Aryabhata explicitly stated that this observed movement is not caused by the stars themselves traveling across the sky, but is instead an illusion resulting from the Earth’s rotation about its own axis. This insight was part of his broader work in spherical astronomy, where he also correctly identified that the Moon and planets shine due to reflected sunlight.21