heliacal

relating to or especially immediately preceding or following the heliacal rising of Canicula (the Dog Star ).

关于天狼星，尤指在天狼星升起前或随天狼星升起。

This star was the most important of the stars to the ancient Egyptians, and the heliacal rising of this star came at the time of inundation and the start of the Egyptian New Year.

这颗星对古及人来讲是最重要的星，而且这颗星与太阳一同升起的时间就是洪及年开始的时间。