Al-Battani

Al-Battani, also known as Albategnius, was a notable Arab astronomer, mathematician, and astronomer who lived from approximately 858 to 929 CE. He is best known for his contributions to astronomy, including his improvements to trigonometry and his work in calculating the length of the solar year. Al-Battani performed detailed observations of the stars and planets, and he made significant advances in the understanding of celestial mechanics.