2年2月 彗星出 牵牛70余日 傅日 牵牛日月 五星所从起 历数之元 三正之始 慧而出之 改更之象也 其出久者 为其事大也
                                                                汉书 天文志
   In the second month of the second year(of Jian Ping ), the comet was out of Altair for more than 70 days. It is said, ‘Comets appear to signify the old being replaced by the new.Altair, the sun, the moon and five stars are in movement to signify the beginning of a new epoch; The beginning of a new year, a new moth and a new day. The appearance of this comet undoubtedly symbolizes change. The extended appearance of this comet indicates that this is of great importance.’
                                Astronomy Records of the Book of the Han Dynasty

   正义牵牛为牺牲，亦为关梁。
                                                            史记 卷27 天宫书
  ‘The primary meaning of Altair, the key supporting pillar of the heavens, is the Perfect Sacrifice.’
                                   Historical Records, Vol. 27, Book of Astronmy

注：汉哀帝刘欣(前7-前1),历称‘建平’年。