唐代瞿昙家族的天文历算活动及其成就

唐代天文学家翟昙罗、瞿昙悉达、瞿昙、瞿昙谦及瞿昙晏祖孙四代,曾三代担任过唐朝太史今、太史监、司天监,领导和主持唐朝官方的天文机构,先后达１１０年以上．他们擅长印度天文历算,也精通中国传统的天文学,编制了《经纬历》、《光宅历》、《甲子元辰历》,编译了印度古代的《九执历》．特别是瞿昙悉达编撰的《开元占经》,引用了不少古代典籍,保存了许多天文资料,介绍了印度古代的数学知识──位值制数码、圆弧量法和弧的正弦,但这些先进的算法因和中国传统算法体系不同,可惜在当时没有引起重视,起到应有的作用．

Qutan familys activities and achievements in astronomy calendar and mathematics in the Tang Dynasty

In the Tang Dynasty, there was a family in which there were five astronomers of four different generations. They were Qutan Luo, Qutan Xida, Qutan Zhuan, Qutan Qian and Qutan Yan. Most of them were appointed to be in charge of astronomical researches covering more than one hundred years during the dynasty. All of them were good both at In dian astronomy, calendar and mathematics and at Chinese astronomy. The books such as "Jingweili", "Guangzhaili', "Jiaziyuanchenlin were compiled by them. One of them also translated and edited the book "Jiuzhili' from acient India. Among them, Qutan Xida should be paid much attention to. He compiled the book "Kaiyuan Zhanjing", and in the book, a lot of books and records were quoted and also a great deal of astronomical materials were recorded. The mathematic knowlages from acient india were too introduced in the book.These advanced algorithms were different from the Chinese traditional system. so that they were not paid attention to then and little influence was exerted.