Title: Opcional

Text: Born in Poland, Copernicus studied mathematics and optics at Kracow. After 30 years of work, he put forward a theory that Earth rotates daily about its own axis, and that Earth and the other planets orbit the Sun with years of different lengths. This challenged the ancient belief that Earth was the center of the Universe. Copernicus was reluctant to publish his controversial theory, but other leading astronomers developed and expanded his theory after his death. Cada párrafo será una prueba.

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