ACRONYCHAL

, or Acronycal, in Astronomy, is said of a star or planet, when it is opposite to the sun. It is from the Greek axronuxos, the point or extremity of night, because the star rose at sun-set, or the beginning of night, and set at sun-rise, or the end of night; and so it shone all the night.

The acronychal is one of the three Greek poetic risings and settings of the stars; and stands distinguished from Cosmical and Heliacal. And by means of which, for want of accurate instruments, and other observations, they might regulate the length of their year. |